JPH09151611A - Reinforcing method for reinforced concrete column - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase a bending strength and a shearing strength easily and efficiently by fixing anchor members to a reinforced concrete column and beam, and winding high strength fiber reinforced sheets on the reinforced concrete column. SOLUTION: Multiple anchor members 4 are attached to the column head part (a) and column leg part (b) of the column 1 of reinforced concrete structure by fixing their one ends 4a, to the reinforced concrete column 1 and their other ends 4b, to the reinforced concrete beams 2, 3, to which the reinforced concrete column 1 is connected. Also high strength fiber reinforced sheets 5 are wound on the reinforced concrete column 1. By this, the bending strength and shearing strength of the column 1 can be increased easily and efficiently. To fix the anchor members 4, their one ends 4a are fixed to the fixing grooves 1a, formed in the side surface of the reinforced concrete column 1 and their other ends 4b are fixed to the fixing holes 2a, 2a, 3a, and 3a formed vertically in the reinforced concrete beams 2 and 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for reinforcing a reinforced concrete column in a reinforced concrete structure, which mainly reinforces the shear strength and bending strength of an existing reinforced concrete column (hereinafter referred to as "column").

[0002]

2. Description of the Related Art Reinforced concrete buildings have been seriously damaged by recent major earthquakes both inside and outside, and shear failure of columns has been pointed out as the primary cause of the damage. And
It was clarified that the cause of increasing the shear rupture was a large number of alternating repeated deformations during strong earthquakes, preventing the column from shear rupture due to such repeated forces, and stabilizing the stability and tenacity of the restoring force characteristics. A recent study has revealed that it is optimal to effectively restrain the concrete (core concrete) in the area surrounded by the main bars to secure it.

On the basis of such an idea, a method of winding a steel plate or a fiber reinforced sheet around the outer periphery of an existing column to increase the shear resistance of the column has already been implemented.

[0004]

However, some of the existing columns have insufficient bending proof stress as well as shear proof stress, and it is sometimes necessary to simultaneously reinforce the bending proof stress and the shear proof stress.

In addition, it has been revealed that the design based on the old seismic resistance standard is not sufficient for the recent large earthquakes both inside and outside the country, and the seismic resistance standard has been reviewed. Since many reinforced concrete buildings still exist, it was necessary to efficiently reinforce the columns of these buildings.

The present invention has been made in response to the above demands, and an object of the present invention is to provide a method for reinforcing a reinforced concrete column which can easily increase the shear strength and bending strength of the reinforced concrete column.

[0007]

According to a first aspect of the present invention, there is provided a reinforcing method for a reinforced concrete column, wherein a plurality of anchor members are provided at one end and a column base of the reinforced concrete column at one end thereof. The other end is fixed and attached to a reinforced concrete beam to which the reinforced concrete column is joined, and a high-strength fiber reinforced sheet is wound around the reinforced concrete column.

According to a second aspect of the present invention, there is provided a method for reinforcing a reinforced concrete column according to the preceding paragraph, wherein one end of the anchor member is fixed to a fixing groove formed on a side surface of the reinforced concrete column, and the other end of the anchor member is fixed. Is fixed to a fixing hole formed perpendicularly to the reinforced concrete beam.

According to a third aspect of the present invention, in the method for reinforcing a reinforced concrete column according to the first aspect, one end of the anchor member is fixed to a fixing groove formed in a side surface portion of the reinforced concrete column, and It is characterized in that the end is fixed to a fixing hole formed obliquely at the joint between the reinforced concrete column and the reinforced concrete beam.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

First Embodiment of the Invention 1 to 3 show an embodiment of the present invention. In the drawings, reference numeral 1 is a column of a reinforced concrete structure constructed in a rectangular cross section, and 2 and 3 are constructed by a reinforced concrete structure, and the upper end of the column 1 is formed. Beams on the upper floor and beams 4 on the lower floor, which are respectively joined to the lower part and the lower part, are attached to the column head a and the column base b of the column 1, respectively, and the joint between the upper end of the column 1 and the beam 2 , And an anchor member that enhances the joint strength between the lower end of the pillar 1 and the beam 3, and the reference numeral 5 is a steel plate or a high-strength fiber reinforced sheet that is wound around the outer circumference of the pillar 1 to shear and reinforce the pillar 1.

The pillar 1 and the beams 2 and 3 are both constructed in a square cross section by conventional conventional reinforced concrete design methods. The pillar 1 may be constructed in a polygonal cross section such as a hexagon or a circular cross section.

The anchor member 4 is formed of a reinforcing bar, a PC steel rod, a PC steel stranded wire or an FRP bar, and has one end thereof.
By fixing 4a to each side surface of the pillar 1 and fixing the other end 4b to the beams 2 and 3, it is mounted so as to straddle between the pillar 1 and the beam 2 and between the pillar 1 and the beam 3, respectively.

In this case, one end 4a of the anchor member 4 has a pillar 1
Is fixed by a high-strength resin adhesive in a fixing groove 1a of a predetermined depth formed continuously on each side surface of the pillar 1 in the axial direction of the pillar 1, and the other end 4b is attached to the beams 2 and 3 on the side surface of the pillar 1. Are vertically formed to a predetermined depth along with and are fixed in the fixing holes 2a and 3a by a high-strength resin adhesive.

The diameter, the number, the pitch and the fixing length of the anchor member 4 are appropriately determined depending on the place.
Further, the fixing groove 1a is formed by the conventional cutting machine and the fixing hole 2a and
3a shall be formed by a conventional drill or the like.

The anchor member 4 may be continuously attached in the axial direction of the column 1 and both ends thereof may be fixed to the beams 2 and 3 respectively (see FIG. 2 (a)).

The steel plate or the high-strength fiber reinforced sheet 5 is wound around the outer periphery of the column 1 once or, if necessary, twice or more. In addition, a constant tension is introduced as needed. Further, the steel plate or the high-strength fiber reinforced sheet 5 is wound in a spiral shape or simply a headband shape (tape shape) continuous in the axial direction of the pillar 1. Further, the high-strength fiber-reinforced sheet 5 is coated or impregnated with a curable synthetic resin material and cured to integrate the pillar 1 and the high-strength fiber-reinforced sheet 5, and at the same time, to easily finish the pillar thereafter. I am doing it.

In the pillar 1 reinforced by the above-mentioned structure, the bending strength is remarkably increased by the anchor member 4 forming a part of the main bar arranged in the concrete of the pillar 1, and also the steel plate or the high strength fiber is used. Due to the confined effect of the reinforcing sheet 5, the shear strength is significantly increased.

Embodiment 2 of the Invention FIG. 4 shows another embodiment of the present invention, in which the other end 4b of the anchor member 4 has a pillar 1
Fixing holes 2b and 3b formed at the joints with the beam 2 and the columns 1 and 3 obliquely toward the center of these joints.
It is fixed by high-strength resin adhesive. Other configurations are almost the same as those of the first embodiment of the invention.

According to this embodiment, the fixing holes 2b and 3b
Is obliquely formed, the pillars 1 do not get in the way when the fixing holes 2b and 3b are formed by a drill, and the fixing holes 2b and 3b can be easily formed.

[0020]

The method of reinforcing a reinforced concrete column according to the present invention is configured as described above, and a plurality of anchor members are fixed to the reinforced concrete column at one end of the column head and the column base of the reinforced concrete column, and The ends are fixed to the reinforced concrete beams to which the reinforced concrete columns are joined and attached respectively, and by winding a high strength fiber reinforced sheet around the reinforced concrete columns, the bending strength and shear strength of the columns can be extremely efficiently and easily increased. There is an effect that can be.

Further, one end of the anchor member is fixed to a fixing groove formed on the side surface of the reinforced concrete column, and the other end of the anchor member is a fixing hole formed vertically to the reinforced concrete beam or between the reinforced concrete column and the reinforced concrete beam. Since the fixing is performed in the fixing hole formed obliquely at the joint portion, there is an effect that both ends of the anchor member can be surely and extremely easily fixed. Furthermore, since the anchor member is embedded in the pillar, the pillar can be made to have no unevenness.

[Brief description of the drawings]

FIG. 1 is a side view of a reinforced concrete column showing an installed state of an anchor member and a high-strength fiber reinforced sheet.

FIG. 2 is a vertical sectional view of a column base portion.

3A is a sectional view taken along line aa in FIG. 1, and FIG. 3B is a sectional view taken along line bb in FIG.

FIG. 4 is a vertical cross-sectional view of a column base portion showing another embodiment.

[Explanation of symbols]

1 columns of reinforced concrete structure, 2 ... beams on the upper floor, 3 ... beams on the lower floor, 4 ... anchor members, 5 ... steel plate or high strength fiber reinforced sheet.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Migame Kobayashi 2-19-1 Tobita-Su, Chofu-shi, Tokyo Kashima Construction Co., Ltd. Technical Research Institute

Claims (3)

[Claims] 1. A plurality of anchor members are fixed to the reinforced concrete pillar at one end and at the other end to a reinforced concrete beam to which the reinforced concrete pillar is joined, at the pillar head and the pillar base of the reinforced concrete pillar, respectively. A method for reinforcing a reinforced concrete column, which comprises mounting and winding a high-strength fiber reinforced sheet around the reinforced concrete column. 2. An anchor member has one end fixed to a fixing groove formed on a side surface of a reinforced concrete column, and the other end of the anchor member fixed to a fixing hole formed perpendicularly to the reinforced concrete beam. A method for reinforcing a reinforced concrete column according to claim 1. 3. One end of the anchor member is fixed to a fixing groove formed on a side surface of the reinforced concrete column, and the other end of the anchor member is fixed to a fixing hole formed obliquely at a joint between the reinforced concrete column and the reinforced concrete beam. The method for reinforcing a reinforced concrete column according to claim 1, wherein the method is fixed.