JPH0774548B2 - Seismic reinforcement structure of RC structure opening - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a seismic reinforcement structure for improving the seismic performance of a reinforced concrete (RC) frame opening.

<Prior art> When constructing a building from reinforced concrete, the cross-sectional area of columns and beams was increased in order to improve seismic performance. In addition, earthquake resistant walls were also installed. However, if the cross-sectional area of columns and beams is increased, the living space will be narrowed and the weight will increase. On the other hand, since the earthquake-resistant wall does not have high toughness, the weight increases due to the need to increase the strength. Especially, although attention is paid to the reinforcement of the opening in the earthquake-resistant wall, a reinforcement method with high toughness was expected. In addition, in the case of a seismic wall, the seismic wall closed the opening and the opening disappeared, which deteriorated usability. This is because the reinforcement efficiency decreases if an opening is provided in the seismic wall.

Therefore, recently, for example, a quadrangular steel frame member that abuts and engages with the inner peripheral surface of a column / beam opening, and both end portions of any one side of the quadrangular steel frame member are provided at substantially the central portion of the other side at the opposite bank position. A toughness-resistant seismic reinforcement structure has been proposed which is composed of a protruding steel bundle or a steel brace obliquely extended and connected to the tip of a steel rod.

That is, a Y-shaped toughness resistant brace is constructed in a square frame member with a brace and a shear panel, and the square frame member measures the stress distribution to reduce damage to the RC frame and the joint portion between the frame member and the RC frame. In addition, the strength and rigidity of the brace are sufficiently increased, and damage is concentrated on the shear panel when an excessive seismic force is applied.

Since the shear panel can secure appropriate strength and large toughness to allow it to buckle prior to the frame members and braces, this allows the shear panel to absorb a large amount of energy during an earthquake, reducing the response deformation of the building and reducing the building's response deformation. Since it functions as a damper to reduce damage, it has a vibration damping effect.

<Problems to be solved by the invention> However, the advantage of this type of seismic reinforcement structure such as the toughness-resistant seismic reinforcement structure described above, that is, the toughness-resistant steel frame brace as exemplified in the prior art Because of its high height, existing RC columns were required to have toughness in order to maximize their advantages.

The present invention has been made in view of the above circumstances, and its purpose is to be able to follow the deformation of the toughness-resistant seismic reinforcing structure applied to the opening while the column holds the axial force,
The purpose is to provide a seismic reinforcement structure for RC openings that can maximize the high toughness of the reinforcement structure.

<< Means for Solving the Problem >> In order to achieve the above-mentioned object, the seismic reinforcement structure of the RC building opening according to the present invention has a frame member on the inner peripheral surface of the existing RC building opening surrounded by columns and beams. In a seismic reinforced structure of an RC building opening in which a Y-shaped toughness resistant brace is provided in close contact with the frame member, at least one of the upper and lower ends of the column,
Notches are provided by cutting a part of the main pillar bars embedded inside. When the column is used without damage, a frame member is provided in close contact with the inner peripheral surface of the existing RC structure opening surrounded by the column and the beam, and the Y-type toughness resistant brace is placed in the frame member. In the seismic reinforcement structure of the RC building opening to be installed, it is made by winding steel plate or reinforcing fiber such as carbon fiber, aramid fiber, etc. around the outer periphery of the column, or of the existing RC building opening surrounded by columns and beams. A frame member is provided in close contact with the inner peripheral surface, and Y is provided in the frame member.
In a seismic strengthening structure of an RC structure opening where a toughness-resistant brace of a mold is arranged, a vertical frame member alone attached to the column of the frame member can bear the axial force that the column originally bears. What has axial strength is used.

<< Operation >> In any of the cases described above, the followability of the column of the opening to the behavior of the toughness-resistant seismic resistant structure is improved, and the toughness of the seismic resistant structure can be efficiently utilized.

<Example> Hereinafter, a preferred example of the present invention will be described in detail with reference to the drawings.

The same reference numerals or the same members in FIGS. 1 to 3 are the same.

FIG. 1 shows a case where a toughness-resistant steel frame seismic resistant structure 4 is applied to a rectangular opening 3 surrounded by columns 1 and beams 2 of reinforced concrete structure (RC structure).

The H-shaped steel is assembled into a similar shape smaller than the opening 3 to form the frame member 5 as a stress transmitting material. The stiffener 6 reinforces the central partial web of the upper horizontal frame located on the upper side of the frame member 5 and both end partial webs of the lower horizontal frame located on the lower side. Further, the shear panel 7 is hung and fixed to the central portion of the upper horizontal frame of the frame member 5, and the braces 8 that are erected obliquely upward from both ends of the lower horizontal frame are connected and fixed to the vertical lower ends of the shear panel 7. .

The steel frame type seismic resistant structure 4 having the above-mentioned configuration does not directly connect the brace 8 in the frame member 5 in the “C” shape, but is in the inverted “Y” shape via the bundle-shaped shear panel 7. The elasticity of 7 improves toughness. When attaching the steel frame type seismic resistant structure 4 to the opening 3, after anchoring the pillars 1 and the beams 2 and attaching the studs to the outer peripheral surface of the frame member 5, the frame member 5 is housed in the opening 3 Non-shrink mortar or the like is placed between the anchor in 3 and the stud on the outer periphery of the frame member 5 to complete the mounting and fixing.

The notch 9 is provided outside the upper and lower ends of the pillar 1-1. The position of the notch 9 may be on the inside or the entire surface of the periphery, but the notch 9 stops within the range in consideration of the axial proof strength of the column, and the notch 9
Can be done when cutting the column main muscle 10 recently. That is, the notch 9 cuts the recent column main bar 10 and leaves the notch made at that time as it is as a void.

Deformation of the column 1 is allowed at the notch 9 and the column main bar 10
Since the column is cut, the stress of the column 1 is reduced, and the deformation of the steel frame type seismic resistant structure 4 is sufficiently followed.

In the embodiment shown in FIG. 2, the frame member 5 is fixed by utilizing the beam 2 having the opening 3 for accommodating the steel frame seismic resistant structure 4.

A carbon fiber 11 is wound around the pillar 1-1 to reinforce its toughness, and in this relationship, the frame member 5 is fixed by attaching the upper and lower horizontal frames to the beam 2-2.

Therefore, if the beam 2 has a sufficient strength, the column 1 is not damaged, and even if the column 1 is forced to undergo a considerably large deformation, the restraining force of the carbon fiber 11 can maintain a sufficient axial force. Therefore, in combination with the action of the frame member 5, the pillars 1 and the beams 2 of the opening 3 can sufficiently follow the deformation of the steel frame seismic resistant structure 4.

FIG. 3 shows still another embodiment. As shown in FIG. 2, when the beam 2-2 does not have sufficient proof stress and it is impossible to damage the column 1-1, the vertical length of the frame member 5 is also increased. Frame 12-12 is as follows.

That is, the vertical frame 12 is strong enough to bear the axial force of the column 1. As a result, since the vertical frame 12-12 is strong, the pillar 1-1 is difficult to break, and even if it is broken, the vertical frame 12 can bear the axial force, so that the building does not collapse.

<Effect> As described in detail above, in the seismic reinforcement structure of the RC building opening according to the present invention, the toughness of the column facing the opening is improved by means such as notches, reinforcing carbon fibers or the vertical frame of the frame member. Therefore, it is possible to integrate with the behavior of the toughness-resistant type seismic reinforcement structure, and it is possible to sufficiently utilize the performance of this type of seismic reinforcement structure.

[Brief description of drawings]

FIG. 1 is a front view illustrating a seismic reinforcement structure of an RC structure according to the present invention, FIG. 2 is a front view illustrating another seismic reinforcement structure, and FIG. 3 is a still another seismic reinforcement structure. It is a front view. 1 ... Pillar, 2 ... Beam 3 ... Opening, 4 ... Steel-frame seismic structure 5 ... Frame member, 6 ... Stiffener 7 ... Shear panel, 8 ... Brace 9 ... Notch, 10 ... Main pillar 11 …… Carbon fiber, 12 …… Vertical frame

Claims (3)

[Claims] 1. An RC structure opening part in which a frame member is closely attached to an inner peripheral surface of an existing RC structure opening surrounded by columns and beams, and a Y-shaped toughness resistant brace is arranged in the frame member. In the seismic reinforcement structure of RC, at least one of the upper and lower ends of the column is provided with a notch by cutting a part of the main bar of the column embedded inside, and the seismic reinforcement structure of the RC building opening. . 2. An RC building opening in which a frame member is provided in close contact with an inner peripheral surface of an existing RC building opening surrounded by columns and beams, and a Y-shaped toughness resistant brace is arranged in the frame member. In the seismic reinforcement structure of, the steel structure or reinforcing fibers such as carbon fiber and aramid fiber are wound around the outer periphery of the column, and the seismic reinforcement structure of the RC structure opening is characterized. 3. An RC structure opening portion in which a frame member is provided in close contact with an inner peripheral surface of an existing RC structure opening surrounded by columns and beams, and a Y-shaped toughness resistant brace is arranged in the frame member. In the seismic retrofit structure, the vertical frame member alone attached to the column of the frame member is provided with an axial force strength capable of bearing the axial force that the column originally bears. Seismic reinforcement structure of RC structure opening.