JP2000328648A - Reinforcing structure of column structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reinforce a beam-column connection section in which a column main reinforcement and a beam main reinforcement are crossed. SOLUTION: A spiral reinforcement 8 is entwined with either one or both of a column main reinforcement 4 and a beam main reinforcement 6 crossing in a beam-column connection section and reinforced thereby. The strength of a column central section surrounded by the column main reinforcement 4, to which shear force by an earthquake or the like is concentrated is increased, and shear strength is improved by installed one or a plurality of the spiral reinforcements 8 inside a hoop reinforcement 5 wound on the column main reinforcement 4 while being directed towards the horizontal direction of the beam main reinforcement.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reinforcing structure for a reinforced concrete column-beam joint in which a column main bar and a beam main bar intersect, and a column main reinforcing bar and a column base reinforcing structure.

[0002]

2. Description of the Related Art Reinforced concrete buildings are designed with columns and beams having a required cross-sectional area based on seismic standards. Even in recent large earthquakes, reinforced concrete buildings built according to current seismic standards showed little brittle destruction of columns and beams themselves, but a number of apparently destructive joints were confirmed. Was.

FIG. 9 shows the structure of a conventional column and beam.
And the beam 2A and the beam 2B orthogonal to the beam 2A intersect to form a beam-column joint 3.

[0004] The column 1 is provided with column main bars 4 vertically arranged at least at four corners, and is wound horizontally in contact with the outer periphery of the column main bar 4 and is provided at intervals vertically. And the hoop muscles 5 (belt muscles) that are provided. The hoop streaks 5 suppress the protrusion of the column main streaks 4 and impart shear resistance to the columns 1. The pillar main bar 4 depends on the cross-sectional area of the pillar 1,
A plurality of bars are arranged between the column main bars 4 and 4 at the four corners.

Further, in order to increase the strength of the column 1, a diagonal hoop 10 which is arranged diagonally and horizontally across the column main reinforcements 4 and 4 which are opposed to each other at a diagonal portion is spaced apart in the vertical direction of the column 1. They are placed and arranged. Further, a sub-hoop 11 is arranged so as to be wound around the opposing sides of the hoop 5 provided horizontally by winding the column main reinforcements 4 and 4 at the four corners and to suppress the protrusion of the hoop 5.

[0006] Beams 2A and 2B intersecting and joining the column 1
Are the upper beam main reinforcement 6, the lower beam main reinforcement 6, and these beam main reinforcements 6.
Are arranged in a stirrup 7 (stirrups). The arrangement interval of the stirrup 7 is made close in the vicinity of the joint with the pillar.

[0007] In such a structure, when a beam-column joint is subjected to seismic force in a reinforced concrete building, the force acting horizontally on the cross section of the column at the beam-column joint causes oblique crushing of the column. Such resultant force is likely to occur, and the resultant force is repeated as positive and negative forces due to the shaking of the earthquake.

[0008] The shear input by this earthquake acts alternately as a compressive and tensile force on the center of the column main bar at the four corners of the column, causing shear failure. For this reason, a crack is generated inside the pillar itself.

[0009] This shearing force is calculated from the moment from the beam end, but it is known that even if the earthquake strength is not so large, it becomes a destructive force exceeding the compressive strength of concrete.

[0010] The shear failure of these beam-column joints 3
When the cross section of the beam 2 is relatively small, or when the beam 2 is eccentrically attached to the column 1, it tends to occur. For this reason, if the design is reworked, such as increasing the cross-sectional area of the column 1, the design plan will be affected.

Japanese Patent Application Laid-Open No. 4-206221 discloses a conventional reinforcing structure for a beam-column joint. In this structure, a reinforced steel plate is wound around the column-beam joint area surrounded by the upper and lower beam main bars, and reinforced over the upper and lower columns above the upper beam main bar and below the lower beam main bar, respectively. It is reinforced by winding a steel plate.

In Japanese Patent Application Laid-Open No. 4-111828, a plurality of reinforcing plates having an opening at the center are horizontally arranged at a required interval vertically at a beam-to-column joint. A reinforcing structure buried in concrete cast at a joint is disclosed. In this structure, the reinforcing plate has an uneven surface in order to increase the adhesive force with concrete, and is reinforced by being connected to and supported by a longitudinal main bar of the column or an auxiliary reinforcing bar. Things.

[0013]

However, in a conventional reinforcing structure in which a reinforcing steel plate is wound or a plurality of reinforcing steel plates are horizontally mounted as in the conventional case, the reinforcing steel plates are prepared in accordance with the respective dimensions of the beam-column joint. There is a problem that it is necessary, the cost is high, and the work of attaching a plurality of reinforcing steel plates to each of the many beam-column joints is troublesome.

Particularly, in the reinforcing structure disclosed in Japanese Patent Application Laid-Open No. 4-206221, a reinforcing steel plate is wound so as to surround columns and beams. The enclosed center S cannot be directly restrained. For this reason, a great reinforcing effect could not be expected even though many steel sheet materials were required.

The present invention has been made in view of the above problems, and can improve the shear strength of a beam-column joint, and can also be applied to a beam-column joint in which reinforcing bars are concentrated in a dense manner. It is an object of the present invention to provide a reinforcement structure for a beam-column joint and a reinforcement structure for a column main reinforcing bar and a column pedestal having good workability.

[0016]

In order to solve the above-mentioned problems, the invention according to claim 1 is to provide a spiral reinforcing bar at one or both of a column main bar and a beam main bar crossing at a beam-column joint. It is characterized by being entangled and reinforced. For this reason, the reinforcement process of the standard work of columns and beams is advanced, and spiral bars are inserted into the beam-column joint from the column-beam joint portion after the standard work is completed, in parallel with the reinforcement process of the standard work. It can be constructed with simple work.

According to a second aspect of the present invention, one or a plurality of the spiral streaks are provided inside the hoop studs wound around the column main streaks in a direction transverse to the beam main streaks. It is characterized by. Therefore, it is possible to increase the strength of the central portion of the column surrounded by the column main bars where the shearing force due to the earthquake is concentrated, and thus it is possible to increase the shear strength.

The invention according to claim 3 is characterized in that the spiral streaks partially project in the direction of the beam main streaks. For this reason, in the present invention, it is possible to increase the bonding strength between the beam and the main bar at the joint between the column and the beam.

According to a fourth aspect of the present invention, one or more spiral muscles are provided inside a hoop muscle wound around the main pillar so as to be directed in the vertical direction of the main pillar. It is characterized by. For this reason, similarly to the invention according to claim 3, the strength of the column central portion surrounded by the column main bar where the shearing force due to the earthquake concentrates can be increased, and therefore, the shear strength can be increased.

Further, the invention according to claim 5 is characterized in that a column main reinforcing bar and / or a vertical line of a column base is wound by a spiral line. For this reason, it is possible to apparently improve the strength of the concrete inside the spiral streak, to prevent the bond splitting failure, and to increase the bonding strength. Therefore, it is possible to prevent the brittle fracture of the member and improve the toughness.

[0021]

1 and 2 show an embodiment of the present invention, in which a column 1, a beam 2A, and a beam 2B orthogonal to the beam 2A are shown.
Intersect to form a beam-to-column joint 3.

The pillar 1 is provided with a pillar main bar 4 extending vertically at least at each of four corners, and is wound horizontally in contact with the outer periphery of the pillar main bar 4, and at equal intervals up and down. Is provided with a hoop muscle 5 (ligament). The hoop bars 5 suppress the protrusion of the column main bars 4 and provide the columns 1 with shear strength. A plurality of column main reinforcements 4 are arranged at equal intervals between the column main reinforcements 4 and 4 at the four corners according to the cross-sectional area of the column 1.

Beams 2A, 2B crossing and joining column 1
Are the upper beam main reinforcement 6, the lower beam main reinforcement 6, and these beam main reinforcements 6.
Is wound around the stirrup 7 (stirrups). The arrangement interval of the stirrups 7 is made dense near the joint with the column in order to increase the strength. Therefore, the beam-to-column joint 3
The so-called panel zone of the crossing beam stirrup 7
And the hoop rein 5 wound around the column main rein 4, the die hoop 10 for reinforcement, the sub hoop 11, and the like (see FIG. 7).

Assembling of each reinforcing bar with respect to the above structure can be performed by the same procedure as in the prior art. For example, the assembling of the rebars can be carried out by standard work such as tying with a binding wire (usually annealed iron wire) or providing a joint between the rebars as necessary.

Here, spiral bars 8 are arranged on the beam-column joint 3 where the arrangement of the bars has been completed in the above-described steps. In this step, the tip of the spiral streaks 8 is entangled and inserted into the upper beam main streaks 6 intersecting at the column-beam joint 3.

Next, the spiral muscle 8 with the tip inserted
By turning the spiral streaks 8 according to the helix, a screw-in state is achieved, and the spiral streaks 8 can be inserted toward the beam main streaks 6. This operation can be performed in a very short time because the spiral reinforcement 8 can be inserted into the conventional reinforcement structure to which a reinforcing steel plate or the like is attached while being entangled with the main beam 6.

[0027] Such insertion is performed by using another spiral muscle 8
This is also performed for b, 8c, and 8d, whereby spiral bars 8, 8b, 8c, and 8d are arranged at the beam-to-column joint 3 of the column 1. Next, the rebars that are entangled with the spiral rebars 8 are tied with binding wires. As shown in FIG. 1, these spiral streaks 8, 8 a, 8 b, and 8 c partially protrude in the direction in which the beam main bars 6 extend. The bonding strength with the column main bar 4 increases.

After the reinforcement of the spiral streaks 8 has been constructed in this way, a normal concrete formwork is assembled and the concrete 9 is poured. Since there is no reinforcing steel plate or the like at the beam-column joint 3 as in the conventional reinforcing method, the concrete 9 can be efficiently filled.

A plurality of spiral bars 8 are provided inside the hoop bar 5 wound around the beam bar 6 and oriented in the lateral direction of the beam bar 6, so that the beam-column joint where the shear force due to the earthquake is concentrated. 3, and the shear strength is remarkably improved.

FIG. 3 is an elevational sectional view showing another embodiment, in which only one spiral streak 8 is used. Only one such spiral streak 8 is used when the column 1 has a relatively small cross section, and is a reinforcing structure used when the interval between the beam-column joint 3 and the main beam 6 is short.

FIG. 4 shows another embodiment of the present invention, in which a column 1, a beam 2A, and a beam 2B orthogonal to the beam 2A intersect to form a column-beam joint 3. In this embodiment, one or a plurality of spiral streaks are provided inside the hoop studs wound around the main pillars at the beam-to-column joint 3 so as to be directed in the vertical direction of the main pillars.

The pillar 1 is provided with a pillar main bar 4 extending vertically at least at each of four corners, and is wound horizontally in contact with the outer periphery of the pillar main bar 4, and at equal intervals up and down. Is provided with a hoop muscle 5 (ligament). The hoop bars 5 suppress the protrusion of the column main bars 4 and provide the columns 1 with shear strength. A plurality of column main reinforcements 4 are arranged at equal intervals between the column main reinforcements 4 and 4 at the four corners according to the cross-sectional area of the column 1.

In order to further increase the strength of the column 1, the diap hoop 10 (see FIG. 7), which is arranged diagonally and horizontally across the column main reinforcements 4, 4, is connected to the column-beam joint 3 or the column. 1. Reinforce the bars at vertical intervals. In addition, the opposing sides of the hoop streaks 5 which are provided by winding the four pillar main streaks 4 and 4 at the four corners, and the sub hoops 11 which are passed over the sides to suppress the protrusion of the hoop streaks 5 and secure the strength. 7) are arranged (not shown in FIG. 4).

Beams 2A and 2B crossing and joining column 1
Are the upper beam main reinforcement 6, the lower beam main reinforcement 6, and these beam main reinforcements 6.
Is wound around the stirrup 7 (stirrups). The arrangement interval of the stirrups 7 is made dense near the joint with the column in order to increase the strength. Therefore, the beam-to-column joint 3
The so-called panel zone of the crossing beam stirrup 7
And the hoop rein 5 wound around the column main rein 4, and the above-described die hoop 10, sub-hoop 11 for reinforcement, and the like.

Assembling of each reinforcing bar with the above structure can be performed by the same procedure as in the prior art. For example, the assembling of the rebars can be carried out by standard work such as tying with a binding wire (usually annealed iron wire) or providing a joint between the rebars as necessary.

Here, spiral bars 8 are arranged on the beam-column joints 3 where the arrangement of the bars has been completed in the above-described steps. In this process, spiral bars 8
Entangle the tip of and insert.

Next, the spiral muscle 8 with the tip inserted
By turning the spiral muscle 8 according to the helix, a screw-in state is obtained, and the spiral muscle 8 can be inserted downward of the column main muscle 4. The stirrup 7 of the beam already arranged below, the hoop of the column and the main bar 4 of the column are entangled, and inserted until reaching the lower main bar 6 of the beam. In this operation, the spiral reinforcement 8 is connected to the column main reinforcement 4 and the hoop reinforcement 5 and the beam main reinforcement 6 intersecting with the conventional reinforcement structure for mounting a reinforcing steel plate or the like.
It can be performed in a very short time because it can be performed simply by inserting it while tangling it with the stirrup 7 or the like.

[0038] Such an insertion is performed with other spiral muscles 8.
This is also performed for b, 8c and 8d, whereby the spiral streaks 8, 8b, 8c and 8d are arranged at the four corners of the pillar 1. Next, the rebars that are entangled with the spiral rebars 8 are tied with binding wires. As shown in FIG.
Since a, 8b and 8c partially protrude in the direction in which the beam main reinforcement 6 extends, the bonding strength between the beam main reinforcement 6 and the column main reinforcement 4 at the joint between the column and the beam increases.

After the arrangement of the spiral streaks 8 has been constructed in this manner, a normal concrete formwork is assembled and the concrete 9 is poured. Since there is no reinforcing steel plate or the like at the beam-column joint 3 as in the conventional reinforcing method, the concrete 9 can be efficiently filled.

A plurality of spiral streaks 8 are provided inside the hoop streaks 5 wound around the column main bars 4 so as to extend in the vertical direction of the column main bars 4, so that the spiral streaks 8 are concentrated on the column main bars 4 where the shearing force due to the earthquake is concentrated. The strength of the enclosed column center portion S is increased, and the shear strength is remarkably improved.

FIG. 5 shows another embodiment of the present invention.
Each of the main reinforcing bars of the column pile is wound with a spiral bar. The spiral muscles may overlap each other. The reinforcement structure of the pillar main reinforcement is also performed by substantially the same steps as those of the embodiment of the reinforcement structure of the beam-to-column joint 3 described above. This, together with the column shear reinforcing bars, apparently improves the concrete strength inside the spiral bars, prevents bond splitting failure, and can increase bond strength, thus preventing brittle fracture of members. And toughness can be improved.

FIG. 6 shows another embodiment of the present invention, similar to FIG. 5, in which a plurality of vertical streaks of a pillar are wound by spiral streaks. The spiral muscles overlap each other. This column base reinforcement structure is also performed by the same process as that of the above-described embodiment of the main reinforcing bar reinforcement structure of the column pile. Thereby, the concrete strength inside the spiral streaks can be apparently improved, the adhesive splitting fracture can be prevented, and the adhesive strength can be increased. Therefore, the brittle fracture of the member can be prevented, and the toughness can be improved.

[0043]

As described above, the reinforcing structure of the beam-column joint of the present invention is wound around the beam main bar and / or the column main bar, and is directed in the lateral direction of the beam main bar and / or the vertical direction of the column main bar. By providing one or a plurality of spiral streaks, the strength of the center of the column surrounded by the column main streaks where the shear force due to the earthquake is concentrated can be increased, and the shear strength can be improved. As a result, the seismic performance of the entire building having the column-beam joint is increased.

Further, since the spiral streaks partially protrude in the direction of the main beam, it is possible to increase the adhesive strength between the column and the beam at the joint between the main beam and the main beam, thereby preventing pull-out.

Further, since the main reinforcing bars of the column pile are wound with spiral bars, the column main bars are reinforced, and together with the column shear reinforcing bars, the concrete strength inside the spiral bars is apparently improved, and the adhesion is improved. Split fracture can be prevented, and the adhesive strength can be increased. Therefore, brittle fracture of the member can be prevented, and toughness can be improved.

Further, since the vertical streak of the column base is wound by a spiral streak, the column base can be reinforced, the concrete strength inside the spiral streak is apparently improved, the adhesive splitting fracture is prevented, and the bond strength is increased. Therefore, the brittle fracture of the member can be prevented, and the toughness can be improved.

Further, since spiral bars formed by spirally processing ordinary reinforcing steel are used, material costs can be kept low. In addition, since the work can be performed in a very short time by inserting the spiral reinforcement while entangled with the main reinforcement of the column and the hoop, or the main reinforcement of the beam and the stirrup, the work cost can be reduced.

Further, a reinforcing process of the standard work of the column and the beam is advanced, and a spiral bar is inserted into the beam-column joint in parallel with the reinforcing process of the standard work from the beam-joint portion after the standard work. Construction time can be shortened.

[Brief description of the drawings]

FIG. 1A is a cross-sectional plan view showing an embodiment of a column-beam joint reinforcing structure according to the present invention. (B) is an elevation sectional view showing one embodiment concerning a reinforcement structure of a beam-column joint of the present invention.

FIG. 2A is a perspective view in an a direction showing an embodiment of a reinforcing structure of a beam-column joint according to the present invention. (B)
1 is a b-direction perspective view showing an embodiment of a column-beam joint reinforcement structure according to the present invention.

FIG. 3 is an elevational sectional view showing a second embodiment of the column-beam joint reinforcing structure according to the present invention.

FIG. 4 is a plan view showing a third embodiment relating to a column-beam joint reinforcing structure of the present invention.

FIG. 5 (a) is a plan sectional view showing an embodiment relating to a reinforcing structure of a main reinforcing bar of a column according to the present invention. It is.

FIG. 6 is a plan sectional view showing an embodiment relating to a column base reinforcing structure of the present invention.

FIG. 7 is a vertical sectional view in an a direction showing an embodiment relating to a column base reinforcing structure of the present invention.

FIG. 8 is a vertical sectional view in the b direction showing an embodiment of the column base reinforcing structure of the present invention.

FIG. 9 is a diagram showing a reinforcement arrangement of a conventional beam-column joint.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 pillar 2 beam 2A, 2B beam 3 pillar-beam connection part 4 pillar main bar 5 hoop bar 6 beam main bar 7 stirrup 8 spiral bar 8a, 8b, 8c spiral bar 9 concrete 10 die hoop 11 sub hoop

Claims (5)

[Claims] 1. A reinforcing structure for a beam-column joint, wherein a spiral bar is entangled with one or both of a column main beam and a beam main bar intersecting at the beam-column joint. 2. The method according to claim 1, wherein one or a plurality of the spiral streaks are provided inside the hoop streaks wound around the column main streaks in a direction transverse to the beam main streaks. The reinforcing structure of the column-beam joint described in the above. 3. The reinforcing structure for a beam-column joint according to claim 1, wherein the spiral streaks partially project in the direction of the beam main streaks. 4. The spiral muscle according to claim 1, wherein one or a plurality of spiral muscles are provided inside the hoop muscle wound around the main pillar so as to be directed in a vertical direction of the main pillar. The reinforcing structure of the column-beam joint described in the above. 5. A reinforcing structure for a column structure, wherein a main reinforcing bar of a column and / or a vertical bar of a column base is wound by a spiral bar.