JP7045135B2 - How to reinforce column-beam joints with bent reinforcing bars and how to control the yield hinge position - Google Patents

Description

The present invention relates to a method of reinforcing a beam-column joint with a bent reinforcing bar and a bent reinforcing bar used for a method of controlling a yield hinge position.

Conventionally, as shown in FIG. 8, the yield hinge generated at the time of an earthquake of the reinforced concrete beam member is generated at a position away from the column surface (the support span is substantially shortened), and the beam end main reinforcement amount is adjusted. A design method for performing rational design by additionally controlling and absorbing energy at an early stage is known.

As the design method, there is a method of adding the main bar amount at the beam end, which is mainly to additionally arrange the cut-off reinforcing bar in parallel with the beam. There is no prior art document that controls the yield hinge position by bending and arranging additional reinforcing bars at the beam-column joint, but the one described in Patent Document 1 is known as the prior art related to the structure of the beam-column joint. Has been done.

Japanese Unexamined Patent Publication No. 2010-185231

However, in the arrangement of the additional reinforcing bars, in order to improve workability, the length of the additional reinforcing bars may be reduced by using mechanical fixing at the tip of the additional reinforcing bars, but the additional reinforcing bars are cut off. Reinforcing bars have the problem that adhesion cracks are likely to occur on the girders. The present invention has been proposed to solve such a problem.

The gist for solving the above-mentioned problems of the method for reinforcing a beam-column joint by a bent reinforcing bar according to the present invention and achieving the object is to arrange reinforcing bars along the main bars of the beam (5) and the column (6) . Each end of the bent rebar (1, 2, 3, 4) and the center of each of the bent rebar that is bent diagonally from both ends of the beam-column joint (7) on the beam (5) side. The bent reinforcing bars (1c, 2c, 3c, 4c) are arranged over the beam (5) , the beam-column joint (7) , and the pillar (6), and the bent reinforcing bars (1 ) are arranged. The central portion (1c, 2c, 3c, 4c) of 2, 3, 4 ) has a length that reaches diagonally from the position of the two-step rebar on the beam (5) side to the position of the two-step rebar on the pillar (6) side. The bent reinforcing bars ( 1, 2, 3, 4) are formed on the beam side (1a, 2a, 3a, 4a) and the column side ends (1b, 2b, 3b, 4b). Fixing nuts (9) for fixing deformed reinforcing bars to increase the adhesion strength to concrete and exert tensile resistance are fixed to each of the bent reinforcing bars (1, 2, 3, 4). The ends on the beam side (1a, 2a, 3a, 4a) are formed vertically symmetrically, and the ends on the column side (1b, 2b, 3b, 4b) are formed symmetrically. ..

At least one end of the bent reinforcing bar arranged on the main bar of the beam is arranged at the position of the first step bar or the second step bar of the beam side main bar.

It includes that a flat plate-shaped reinforcing member is fixed to a portion where diagonally bent portions of the bent reinforcing bar intersect.

The gist for solving the above-mentioned problem of the method for controlling the position of the yield hinge by the bent reinforcing bar according to the present invention and achieving the object is to control the position of the yield hinge in the beam by the method for reinforcing the column-beam joint described above. That is.

According to the method of reinforcing the beam-column joint by the bent reinforcing bar and the method of controlling the position of the yield hinge, the position of the yield hinge of the beam is controlled, which contributes to the damage control of the beam-column joint and the attachment of the additional reinforcing bar. It has the excellent effect of improving performance and reducing damage to the beam. Further, the bending reinforcing bar bears a part of the shearing force generated in the beam-column joint, so that the strength of the beam-column joint can be improved. By fixing a flat plate-shaped reinforcing member at the intersection of the bent reinforcing bars, it is possible to improve the flat fit.

It is a vertical sectional view (A) and the side view (B) of the bent reinforcing bar 1 and 2 which shows the Example of the method of reinforcing a column-beam joint part by the bent reinforcing bar which concerns on this invention. It is a vertical cross-sectional view which shows the Example which arranged the bent reinforcing bars 1 and 2 in the position of the 1st step bar 5a which concerns on the main bar shown in FIG. Vertical cross-sectional view (A) of an example in which the bent reinforcing bars 1 and 2 according to the present invention have hook portions formed at their ends, and the bent reinforcing bars 1 and 2 are located at the positions of the one-step reinforcing bars 5a on the main reinforcing bars. It is a vertical sectional view (B) which shows the arranged example. It is a vertical cross-sectional view which shows the other example of the reinforcement method of the column-beam joint part which concerns on this invention. It is a side view (A), (B) which shows the bent reinforcing bars 1 to 4 which concerns on another Example shown in FIG. 4 in the arrangement in the use state. It is a vertical cross-sectional view which shows the Example which arranged the arrangement of the bending reinforcing bars 1 to 4 shown in FIG. 4 at the position of a 1st step bar in the method of reinforcing a beam-column joint part by the bending reinforcing bar which concerns on this invention. It is a partially enlarged explanatory view which shows the use state of the reinforcing member 8 in the method of reinforcing a beam-column joint which concerns on this invention. It is a vertical sectional view explaining an example of the reinforcement method of the column-beam joint part by the conventional bent reinforcing bar.

In the method for reinforcing a beam-column joint portion by a bent reinforcing bar according to the present invention, as shown in FIG. 1, the bent reinforcing bars are crossed and arranged inside the beam-column joint portion.

The bent reinforcing bar used for the reinforcing structure of the beam-column joint will be described above. As shown in FIGS. 1A and 1B, the bent reinforcing bars 1 and 2 include both end portions 1a and 2a of the bent reinforcing bars arranged along the main reinforcing bar of the beam and the end portions on the beam side. It is formed by a fixing nut 9 provided in the above and central portions 1c and 2c which are bent diagonally and arranged in a beam-column joint 7.

The both end portions 1a and 2a are arranged at the positions of the two-step bars with respect to the one-step bars 5a of the beam main bar, respectively. The central portions 1c and 2c have lengths that reach from the ends of the beams on both the left and right sides to the positions of the upper and lower two-step streaks, respectively.

By arranging the bent reinforcing bars 1 and 2 to the beam 5 and the beam-column joint 7, the adhesion performance with concrete is improved, and a part of the shearing force in the beam-column joint 7 is borne. It is effective in controlling damage to the beam-column joint 7. It also controls the position of the yield hinge on the beam 5.

As shown in FIG. 2, the positions of both ends of the bent reinforcing bars 1 and 2 are arranged according to the position of the 1st step bar 5a, not the position corresponding to the 2nd step bar of the main bar of the beam 5. Is. In this case, the lengths of the central portions 1c and 2c are also the lengths that reach the positions of the upper and lower one-step bars from the end portions of the beams, respectively. By doing so, it is possible to control the position where the yield hinge of the beam 5 is generated.

As shown in FIG. 3A, hook portions 1d and 2d bent toward the center in the vertical direction of the beam 5 are formed on the tip side of the bent reinforcing bars 1 and 2 instead of the fixing nut 9. Is. The ends 1a and 2a on the beam side are arranged at the positions of the two-step bars of the beam main bar. As described above, since it is only necessary to process the end portion of the bent reinforcing bar and arrange the reinforcing bar without using the fixing nut 9, the number of parts is reduced and the workability is improved. As shown in FIG. 3B, the ends 1a and 2a on the beam side can be arranged at the position of the one-step bar of the beam main bar. This is to control damage to the beam-column joint 7.

As shown in FIGS. 4 to 5, the bent reinforcing bars 1 to 4 are arranged along the main bars of the beam and the column at both ends of the bent reinforcing bar and both end faces of the beam side of the beam-column joint. It is the central part of the bent reinforcing bar that is bent diagonally from the beam 5, and this is arranged over the beam 5, the beam-column joint, and the column 6.

Of these, for example, the bent reinforcing bar 1 is the column at both end portions 1a and 1b of the bent reinforcing bar arranged along the main bars of the beam 5 and the column 6 and the beam-column joint portion 7. It is a central portion 1c of a bent reinforcing bar that is obliquely bent from the end surface of the beam joint portion 7 on the beam side to the end surface of the column beam joint portion 7 on the column side.

The central portion 1c of the bent reinforcing bar 1 is formed to have a length that diagonally reaches from the position of the two-step bar 5b on the beam side to the position of the two-step bar on the column side. Alternatively, the length is formed so as to reach diagonally from the position of the 1-step bar 5a on the beam side to the position of the 1-step bar on the column side.

Similar to the bent reinforcing bar 1, as shown in FIGS. 5A and 5B, the bent reinforcing bar 2 is formed vertically symmetrically, and the bent reinforcing bars 3 and 4 are formed symmetrically. A well-known fixing nut 9 for fixing the deformed reinforcing bar is fixed to the tip of each of the bent reinforcing bars 1 to 4, and the adhesive strength to the concrete is increased to exert the tensile resistance. There is.

As shown in FIG. 4, the method for reinforcing the column-beam joint according to the present invention is that the bent reinforcing bars 1 to 4 in the column-beam joint 7 are located at the positions of the two-step bars 5b or the one-step bars 5a on the beam side. In addition, on the pillar side, the end portion is arranged and fixed at the position of the two-step reinforcing bar. In the column-beam joint portion 7, the central portions 1c to 4c of the bent reinforcing bars 1 to 4 are arranged so as to intersect each other when viewed from the horizontal direction orthogonal to the direction of the beam 5.

In this way, the bent reinforcing bars 1 to 4 were arranged so as to intersect the beam-column joint 7, and the reinforcing bars were added over the beam 5, so that the yield hinge position of the beam was set away from the column surface. In addition to being generated, damage to the beam-column joint is reduced by bearing a part of the shearing force generated in the beam-column joint 7.

As shown in FIG. 6, as another embodiment, the orientation of the central portions 1c to 4c of the bent reinforcing bars 1 to 4 is changed, for example, from the 1st step bar on the beam side to the 2nd step bar on the column side. Bent reinforcing bars 1 to 4 are formed so that the reinforcing bars can be arranged. It is also possible to arrange the bent reinforcing bars 1 to 4 on the columns / beams to form a reinforcing method in which the bent reinforcing bars 1 to 4 intersect at the column-beam joint portion 7. In this way, by arranging the bent reinforcing bars on the columns, it is effective in improving the strength of the columns.

Such other embodiments are performed to facilitate the reinforcement construction, to facilitate the concrete placement, or to shear the building, depending on the reinforcement arrangement of the reinforcing bars in the beams 5 and the columns 6. It is possible to flexibly arrange the bent reinforcing bars by constructing them according to the load conditions of the force.

As shown in FIG. 7, the structure is such that the flat plate-shaped reinforcing member 8 is fixed at the intersection of the central portions 1c and 2c, which are the diagonally bent portions of the bent reinforcing bars 1 and 2. By providing such a reinforcing member 8, the flat fit can be improved.

The method for reinforcing the beam-column joint and the method for controlling the yield hinge position according to the present invention can be widely applied to the beam-column joint of RC structure.

1 Bent rebar, 1a Beam side end,
1b Column side end, 1c Column-beam joint center,
1d hook part,
2 Folded rebar, 2a Beam side end,
2b Column side end, 2c Column-beam joint center,
2d hook part,
3 Folded rebar, 3a Beam side end,
3b Column side end, 3c Column-beam joint center,
4 Folded rebar, 4a Beam side end,
4b Column side end, 4c Column-beam joint center,
5 beams, 5a 1-step bars,
5b 2-step muscle,
6 pillars,
7 Column-beam joint,
8 Reinforcing members,
9 Fixing nut.

Claims (3)

Both ends of the bent reinforcing bars (1, 2, 3, 4) arranged along the main bars of the beam (5) and the column (6) , and the beam (5) of the beam-column joint (7) . The bent reinforcing bars, which are the central portions (1c, 2c, 3c, 4c) of the bent reinforcing bars that are bent diagonally from both end faces on the side, are the beam (5) , the beam-column joint (7) , and the column . Reinforcing bars are arranged over (6) ,
The central portion (1c, 2c, 3c, 4c) of the bent reinforcing bar (1, 2, 3, 4 ) is a two-step bar on the column (6) side from the position of the two-step bar on the beam (5) side. It is formed to a length that reaches the position diagonally,
The ends (1a, 2a, 3a, 4a) on the beam side and the ends (1b, 2b, 3b, 4b) on the column side of the bent reinforcing bars (1 , 2, 3, 4) are made of concrete. Fixing nuts (9) for fixing deformed reinforcing bars to increase adhesion strength and exert tensile resistance are fixed , respectively .
The beam-side ends (1a, 2a, 3a, 4a) of the bent reinforcing bars (1, 2, 3, 4) are formed vertically symmetrically, and the column-side ends (1b, 2b, 3b, 4b) means that they are formed symmetrically.
A method of reinforcing beam-column joints with bent reinforcing bars. A flat plate-shaped reinforcing member is fixed at the intersection of the diagonally bent parts of the bent reinforcing bar.
The method for reinforcing a beam-column joint by a bent reinforcing bar according to claim 1 . Controlling the position of the yield hinge on the beam by the method for reinforcing the beam-column joint according to any one of claims 1 and 2 .
A method of controlling the yield hinge position by a bent reinforcing bar.

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