JP6515120B2 - Reinforcement method - Google Patents

Description

The present invention relates to a reinforcement method.

Structural rebars need to be arranged at positions where a predetermined cover thickness is secured from the surface of the concrete structure for the purpose of corrosion prevention.
Although the cover concrete portion is generally formed so as not to contain metal or the like from the viewpoint of securing the quality, in order to prevent cracking of the surface portion of the concrete structure, small diameter reinforcing bars ( There may be a case where the crack control rebar is placed.

Like the structural rebar, this crack control rebar also needs to be arranged at a position where a predetermined cover thickness is secured from the surface of the concrete structure for the purpose of preventing corrosion.
Therefore, when constructing a concrete structure, it is general to install a spacer between the reinforcing bar and the formwork to secure a necessary cover thickness.

In concrete structures in which reinforcing bars are arranged in two rows, such as structural reinforcing bars and crack control bars, spacers for double row reinforcing bars are used.
As a spacer for two-step reinforcement, for example, as shown in Patent Document 1, a mortar portion formed so as to be able to mount the lower row reinforcement and a steel wire processed portion formed to be able to mount the upper row reinforcement There are upper and lower rib spacers configured.
Further, Patent Document 2 discloses a rebar spacer formed so as to be capable of mounting a rebar, which is formed so as to be capable of being stacked in a plurality of stages.

JP 2011-12530 A Utility model registration No. 3167995 gazette

In the case of performing two-stage reinforcement using a conventional spacer, it is necessary to pre-set a lower rebar (rebar for crack control). If the lower reinforcement is pre-assembled, the lower reinforcement will be an obstacle in the assembly work of the upper reinforcement (structural reinforcement).
In addition, it is necessary to carry out the work of assembling the upper reinforcements carefully so as not to cause damage or deviation in the lower reinforcements.

As described above, it took time and effort to arrange the bars by interposing the spacer on the lower side of the reinforcing bar.
From this point of view, the present invention aims to propose a reinforcement method which enables to perform the Haisuji work easily.

In order to solve the above problems, in the reinforcement method of the present invention, a reinforcement spacer provided with a main body portion and a locking portion is engaged with a reinforcing bar, the reinforcing bar is lifted, and the reinforcement spacer is And a rotating step. Further, in the reinforcement method, a step of lowering the reinforcing bar in a state in which the reinforcement spacer is hung and placing the reinforcing bar on the reinforcement spacer installed or the reinforcement installed The method further comprises the step of placing the reinforcing bar on a spacer and arranging the reinforcing bar to a predetermined height .

According to reinforcement method of the present invention, it is possible to perform Haisuji work easily.

It is a sectional view showing a concrete structure of an embodiment of the present invention. It is a perspective view of the spacer for reinforcement bars. (A) is a front view of the state which stood the spacer for reinforcement, and (b) is a front view of the state which turned down the spacer for reinforcement horizontally. It is a figure which shows the temporary placement process of the wire arrangement method of this embodiment, Comprising: (a) is a front view, (b) is a longitudinal cross-sectional view. It is a figure which shows the assembly process, Comprising: (a) is a front view, (b) is a longitudinal view. It is a figure which shows the same bar arrangement process, Comprising: (a) is a front view, (b) is a longitudinal view.

In an embodiment of the present invention, as shown in FIG. 1, the concrete head portion of the structure reinforcement 2 (upper reinforcing bars for cover thickness t _1), a predetermined cover thickness (the lower reinforcing bar for cover thickness t ₂₎ A spacer for reinforcement used when constructing the reinforced concrete structure 1 having the crack control rebar 3 arranged therein and a reinforcement method using the spacer for reinforcement will be described.

The reinforcement spacer 10 has a main body 11 and a locking portion 12 as shown in FIG. The main body portion 11 and the locking portion 12 are both made of a non-corrosive material.
Body portion 11 is formed of a mortar made of a block having the same height as the lower reinforcement for head thickness t _2. The main body portion 11 of the present embodiment is a cube (square pole), but the shape of the main body portion 11 is flat at the bottom and is required for the crack control rebar 3 (cover thickness t ₂ for lower rebar It is not limited as long as it is a columnar member having a height corresponding to 1), and may be, for example, a rectangular parallelepiped, a cylinder, or a frustum. Moreover, the material which comprises the main-body part 11 is not limited to mortar, For example, resin may be sufficient.

The locking portion 12 has a pair of wedge-shaped pieces 13, 13 provided to protrude on the upper surface of the main body portion 11. Note that the locking portion 12 does not have to be wedge-shaped as long as locking to the reinforcing bar is possible. Although the locking portion 12 is made of resin, the material constituting the locking portion 12 is not limited to resin as long as it is non-corrosive.
It is desirable that the outer surface (the surface opposite to the other wedge-shaped piece 13) of each wedge-shaped piece 13 be formed as close as possible to the extension surface of the side face of the main body 11.

One end of the locking portion 12 protrudes from the upper surface of the main body 11, and the other end is embedded in the main body 11.
The locking portion 12 may be formed by embedding two independent wedge-shaped pieces 13 into the main body portion 11, respectively, or the lower portion of the U-shaped member (the portion opposite to the opening side) ) May be embedded in the main body 11.

  One end of the wedge-shaped piece 13 is bent toward the center side (the other wedge-shaped piece 13 side) of the main body portion 11 so that the tip is lower than the upper end. The tip end portions of the pair of wedge-shaped pieces 13 are inclined so that the distance between them becomes narrower as it goes downward. That is, the tip end portions of the pair of wedge-shaped pieces 13 have an inverted V shape. In the present embodiment, one end of the wedge-shaped piece 13 is bent in an arc shape, but the shape of the wedge-shaped piece 13 is not limited, and may be bent at an acute angle, for example.

A gap 14 smaller than the diameter of the crack control rebar 3 is formed between the tips of the pair of wedge-shaped pieces 13, 13.
The crack control rebar 3 is inserted between the wedge-shaped pieces 13 as shown in FIG. 3A by inserting the gap 14. Since the width of the gap 14 is smaller than the diameter of the crack control rebar 3, even if the crack control rebar 3 inserted between the wedge pieces 13 is pulled upward, the wedge piece 13 And is unlikely to get out of the gap 14.

Hereinafter, the reinforcement method using the spacer 10 for reinforcement is demonstrated.
In this embodiment, the case where reinforcement bars 2 and 3 (refer to Drawing 1) by the side of the undersurface of concrete structure 1 are arranged is illustrated.
The reinforcement method of the present embodiment includes a temporary placement step, an assembly step, and a reinforcement step.

The temporary placement step, as shown in FIGS. 4 (a) and 4 (b), is a step of temporarily placing the crack control rebar 3 on the formwork or on the ground (hereinafter simply referred to as "floor 4"). .
In the temporary placement step, first, as shown in FIG. 3A, the reinforcement spacer 10 is engaged with the crack control rebar 3.

When locking the reinforcement spacer 10 to the reinforcing bar 3, the crack control reinforcing bar 3 is inserted into the gap 14 from above the locking portion 12. When the tip of the pair of wedge-shaped pieces 13 and 13 is cracked and the outer peripheral surface of the reinforcing bar 3 for control is pressed, the resin-made wedge-shaped piece 13 is outside (the opposite side to the other wedge-shaped piece 13) Since 14 is expanded, the crack control rebar 3 passes through the gap 14.
The crack control rebar 3 that has passed through the gap 14 is disposed in the space surrounded by the locking portion 12.

Next, as shown in FIGS. 3 (b) and 4 (a), the crack control rebar 3 is temporarily placed in a state where the reinforcement spacer 10 is turned to the side.
The crack control rebar 3 is disposed at a position close to the floor surface 4 by laying the reinforcement spacer 10 sideways.

  Subsequently, as shown in FIG. 4 (b), the crack control rebar 3b is placed on the crack control rebar in a direction intersecting with the crack control rebar 3a to which the rebar spacer 10 is engaged. Assemble the crack control bars 3 in a grid.

The assembling step is a step of assembling the structural rebar 2 above the crack control rebar 3 as shown in FIGS. 5 (a) and 5 (b).
The structural rebar 2 is arranged in a grid at a predetermined pitch. At this time, since the crack control rebar 3 is temporarily placed at a position close to the floor surface 4, the distance between the crack control rebar 3 and the structural rebar 2 is such that the crack control rebar 3 is arranged at a predetermined position. It becomes bigger than it is.

The reinforcement step is a step of arranging the crack control rebar 3 below the structural rebar 2 as shown in FIGS. 6 (a) and 6 (b).
In the reinforcement process, first, the reinforcement control spacer 3 is erected by pulling up the temporarily placed crack control rebar 3.

Next, the crack control rebar 3 is lowered in a state in which the reinforcement spacer 10 is erected (a state in which the reinforcement spacer 10 is hung on the crack control reinforcement 3), and the crack control reinforcement 3 is used for reinforcement It is placed on the upper surface of the main body 11 of the spacer 10. When placing the crack control in reinforcement spacers 10, the lower reinforcement for head thickness t ₂ equal gap is secured between the crack control reinforcement 3 and the floor 4.

As described above, according to the reinforcement method of the present embodiment, a sufficient gap can be secured between the structural rebar 2 and the crack control rebar 3 when arranging the structural rebar 2, so the crack control rebar 3 There is no problem with the arrangement of the structural rebar 2 and it is easy to work.
In addition, it is possible to arrange the crack control reinforcement at a predetermined position only by erecting the reinforcement reinforcement spacer 10 erected at the time of the reinforcement of the structural reinforcement 2 so that the workability is excellent. .

  Since the crack control rebar 3 in which the rebar spacer 10 is engaged is brought close to the floor surface 4 by laying the rebar spacer 10 sideways, the worker when laying out the structural rebar 2 Even if a crack or the like is accidentally placed on the crack control rebar 3, the possibility that the crack control rebar 3 is largely bent or the like is unlikely to occur.

  The reinforcement spacer 10 is configured to be less likely to fall off from the crack control rebar 3, so that the reinforcement spacer 10 may fall even if the crack control reinforcement 3 is pulled up in the reinforcement step. Absent.

The reinforcement spacer 10 simply rotates the crack control reinforcement 3 as its axis by its own weight only by lifting the crack control reinforcement 3 in the reinforcement process, and is in a predetermined installation state, and therefore, is excellent in workability.
Moreover, since the reinforcement spacers 10 are made of a non-corrosive material, they do not corrode even if they are disposed in the cover concrete.
Further, since the bottom surface of the reinforcement spacer 10 is flat, it is stable when erected.

  When the reinforcement spacer 10 is used, the crack control rebar 3 is arranged in the cover concrete of the structural rebar 2 so that the crack on the surface of the concrete structure 1 is controlled, and the concrete structure 1 is excellent in durability Can be built.

As mentioned above, although embodiment of this invention was described, this invention is not limited to above-mentioned embodiment, About each said component, in the range which does not deviate from the meaning of this invention, it can change suitably.
The concrete structure formed using the reinforcement method of this embodiment is not limited, For example, a floor slab, a footing, a beam, etc. are employable.

Although the said embodiment demonstrated the case where a concrete structure which has a crack control rebar was constructed, the concrete structure which can apply the reinforcement method of this invention does not necessarily need to have a crack control rebar.

  Although the said embodiment demonstrated the case where the lower reinforcement (rebar 3 for crack control) was a diameter smaller than the reinforcement (structural reinforcement 2) of the upper row, the reinforcement diameters of upper and lower reinforcements are not limited, For example, the same rebar diameter may be used.

  The locking portion 12 of the reinforcement spacer 10 need not necessarily have the pair of wedge-shaped pieces 13 as long as it can be locked to the crack control rebar 3 (lower rebar). For example, one hook-like member may be used.

Reference Signs List 1 concrete structure 2 structural rebar 3 crack control rebar 10 rebar spacer 11 main body 12 locking portion 13 wedge portion 14 clearance t ₁ cover thickness for upper rebar t ₂ cover thickness for lower rebar

Claims (2)

Locking the reinforcement spacer comprising the main body portion and the locking portion to the reinforcing bar;
Lifting the rebar and rotating the rebar arrangement spacer;
And a step of lowering the reinforcing bar in a state in which the reinforcing bar spacer is hanging, and placing the reinforcing bar on the erected reinforcing bar spacer. Locking the reinforcement spacer comprising the main body portion and the locking portion to the reinforcing bar;
Pulling up the rebar and rotating the rebar arrangement spacer;
Placing the reinforcing bar on the standing reinforcing bar and arranging the reinforcing bar at a predetermined height.

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