JPH086401B2 - Shear reinforcement - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape of a shear reinforcing bar with a hook used for an RC structure.

[0002]

2. Description of the Related Art When a column or beam of a reinforced concrete building has an RC structure, a shear reinforcing bar called a hoop or stirrup surrounding the main bar arranged in the longitudinal direction of the column or beam surrounds the main bar. And bury it in concrete. Conventionally, such a shear reinforcing bar has a shape obtained by bending a deformed reinforcing bar into a square or rectangular shape surrounding the outer periphery of the main bar 10 as shown in FIG. Had formed.

[0003]

FIG. 4 is a cross-sectional view of a column 3 having an RC structure in which such a main bar 10 and a conventional shear reinforcing bar 1 are combined. FIG. 4B shows a pattern in which the concrete 4 of the pillar 3 having the cross section shown in FIG. 4A is destroyed during an earthquake. RC using shear reinforcement with hook
In the process in which a structural pillar or beam is destroyed by a strong earthquake, first, as shown in FIG. 4B, the concrete 5 at the four corners of the pillar or beam is missing, and the shear reinforcing bar and the main bar 10 are exposed. . After that, as shown in FIG. 4 (c), it is known that the shear reinforcing bar 1 causes a moment 7 to act on the portion of the hook 2 by pulling, causing deformation 6 of the hook, and finally breaking.

Therefore, in order to solve the problems of the conventional shear reinforcing bar with a hook, as shown in FIG. 3, a shear reinforcing bar of a welded structure without hooks has begun to be used. However, the shear reinforcing bar of the welded structure has a problem that it requires a lot of time and effort for welding, the tensile strength of the welded portion is lower than that of other portions, and the heat-affected zone exhibits brittleness, resulting in poor toughness. An object of the present invention is to provide a shape of a shear reinforcing bar that solves these conventional problems.

[0005]

Means for Solving the Problems Conventionally, the hook portion of the shear reinforcing bar with a hook was attached to the main bars at the four corners of the column or beam, but in the present invention, the hook section is locked to the main bars other than the four corners.
That is, the present invention relates to a shear reinforcing bar with a hook used for an RC structure, in which both ends of one shear reinforcing bar surrounding the main bar are attached.
Located the position of the formed hook other than the four corners of the pillar or beam
It is provided in the part that locks to the same main bar , and the hook is bent
The shear reinforcing bar is characterized by having an angle of 135 ° or more .

[0006]

[Operation] The shear reinforcement of the present invention is one shearing wire surrounding the main reinforcement.
Since the hooks formed at both ends of the breaking reinforcing bar are locked to the same main bars other than the four corners, even if the RC structure columns and beams under earthquake load lose the concrete at the four corners, shear strengthening is performed. The hook part of the muscle is not exposed to the outside. Therefore, the hook is not deformed and the performance as the shear reinforcing bar is not lost. Also, since it is not a welded structure, it requires less labor and is highly reliable.

[0007]

1 is a schematic view of an embodiment of the present invention. The shear reinforcing bar 8 has a shape in which a hook 9 is engaged with a main bar 11 located at positions apart from four corners. The bending angle of this hook is 180 °. Such shear reinforcements 8 are
Even if the concrete in the corner is missing, the hook is left firmly fixed to the main bar 11 where it does not drop, and it acts up to the limit of the tensile strength of the shear reinforcing bar against the destruction of columns and beams. The reliability is significantly higher than that of the shear reinforcement with hook and the shear reinforcement of welded structure.

[0008]

As described above, according to the present invention, since the hook is surely kept in the state of being locked to the main bar, it greatly contributes to the improvement of the toughness of the RC structure column or beam.

[Brief description of drawings]

FIG. 1 is a plan view of a shear reinforcing bar of an example.

FIG. 2 is a plan view of a conventional shear reinforcing bar.

FIG. 3 is a plan view of the shear reinforcing bar of the welded structure.

FIG. 4 is an explanatory diagram showing destruction in the RC structure.

[Explanation of symbols]

 1 Shear Reinforcing Bar 2 Hook 3 RC Structural Column 4 Concrete 5 Missing 6 Deformation of Hook 7 Moment 8 Shear Reinforcing Bar 9 Hook 10, 11 Main Bar

Claims (1)

[Claims] 1. A shear reinforcing bar with a hook used for an RC structure, which is formed at both ends of a single shear reinforcing bar surrounding a main bar.
The position of the hook is the same except for the four corners of the pillar or beam.
Bent angle of the hook provided on the part that locks to the main bar of the
The shear reinforcement bar is characterized by having a temperature of 135 ° or more .