JP2001027048A - Earthquake resistant reinforcing method for existing building by rc earthquake resistant wall - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve earthquake resistance by adhering a channel steel-made frame material to the inner face of a column beam frame in a manner the channel shape faces inward, and expanding an earthquake resistant wall having an anchor bar projecting from a channel bottom. SOLUTION: The channel shape of a remarkably large channel steel-made steel-frame material 4 as compared with the wall thickness of an RC earthquake resistant wall 3 is arranged in substantially the same length as the inner size of a column 1 or a beam 2 on a frame inner face comprising the column 1 and the beam 2 in a manner facing inward. Next, the frame 4 is adhered to the column and beam frame by an adhesive 5, and a wall 3 projecting an anchor bar is extended inward from the channel bottom of the frame 4. In addition, in accordance with request, the frame 4 is adhered to be arranged on the four circumferences of the wall 3 along the inner face of the upper and lower beams 2 and the right and left columns 1 or adhered to be arranged along the inner face of the upper and lower beams 2. Furthermore, if the frame 4 is a material having a sufficient wide flat face on the firm adhesion of the column 1 and the beam 2 without being limited to the channel type steel material, it may be a flat steel plate, a T-shape steel, a hat-shaped steel or the like. Thereby earthquake resistance can be improved, and since noise and vibration are low, construction can be performed as one sits.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a method of retrofitting an existing building by adding a reinforced concrete shear wall (hereinafter referred to as RC shear wall).

[0002]

2. Description of the Related Art After the Great Hanshin Earthquake, the need for seismic reinforcement of existing buildings designed according to the old standards was recognized again. However, despite the growing awareness, the implementation of seismic retrofitting of existing buildings has not progressed much. It is said that the reason for this is that the use of existing buildings during the construction period is greatly restricted by noise during the construction.

[0003] In other words, various construction methods have been developed and implemented as seismic reinforcement methods for existing buildings, but reinforcement methods by adding RC shear walls are the most common, and there are many examples. However, the method of integrating these with the existing building structure, whether it is the seismic strengthening method by adding RC shear walls or the steel frame braces, is to remove the existing finish and roughen Since each process of anchoring is indispensable and generates a great deal of noise and vibration, it is not in a condition where the construction can be carried out "as is".

[0004] The delay in the spread of seismic retrofitting of existing buildings is a serious social problem.

Conventionally, by solving the above-mentioned noise and vibration problems,
As a technique that enables “in-place” construction, for example, a method for mounting a seismic element for reinforcement of an existing building described in Japanese Patent Application Laid-Open No. 58-146663 is known. In this seismic retrofitting method, a plurality of mounting metal pieces having a U-shaped cross section are arranged on columns and upper beams in a discontinuous manner at intervals necessary for the injection of adhesive, in a direction to embrace the columns or beams. And fix them with an adhesive. On the lower beam (on the slab), a plurality of flat plate-shaped mounting hardware are also discontinuously arranged at intervals necessary for the injection of the adhesive, and each is fixed with the adhesive. A fixing reinforcing bar or a steel material is attached to each mounting hardware in advance. Thereafter, the reinforcing steel for the wall is fixed to the reinforcing steel or the like, and concrete is cast, thereby adding an earthquake-resistant wall.

[0006]

In the above-mentioned known seismic retrofitting method, a large number of piece-shaped fittings must be attached to pillars and beams with adhesives one by one. bad. In addition, the mounting hardware is only an element that works to connect the RC for the RC shear-resistant wall to the beam-column frame via fixing steel, etc. It cannot be a stress transmitting element. Therefore, when an excessive stress due to an earthquake or the like is received, local destruction of the outer peripheral portion of the RC shear wall cannot be prevented, and there is a concern that the RC shear wall does not truly function as a seismic reinforcement element.

[0007] An object of the present invention is to provide an additional RC shear wall.
The structure is such that the outer peripheral part is restrained by steel frame material to prevent local destruction, and furthermore, it is a structure that reliably transmits excessive stress due to earthquakes etc. between the column and the beam frame. It is an object of the present invention to provide a method for retrofitting an existing building with RC shear walls, which is effective for the retrofitting of existing buildings.

[0008]

According to a first aspect of the present invention, there is provided a seismic retrofitting method for an existing building using an RC shear wall according to the first aspect of the present invention.
A seismic retrofitting method for an existing building with additional earthquake-resistant walls, in which the length of a channel along the inner surface of a beam-to-column frame is approximately equal to the internal dimension of the column or beam, and is considerably larger than the wall thickness of the earthquake-resistant wall. A steel frame member made of a shape-like material, its groove shape is arranged inwardly and bonded to a beam-column frame, and an earthquake-resistant wall having an anchor bar projecting inward from the groove bottom of the steel frame member is added. It is characterized by reinforcement.

According to a second aspect of the present invention, there is provided a method for reinforcing an existing building by using the RC shear wall according to the first aspect,
The steel frame material is arranged and bonded along the inner surfaces of the upper and lower beams, or along the inner surfaces of the upper and lower beams and the left and right columns.

According to a third aspect of the present invention, there is provided a method for reinforcing an existing building by the RC shear wall according to the first aspect,
The steel frame material is a flat steel plate having a flat adhesive surface, a T-shaped steel shape, or a hat-shaped steel material.

According to a fourth aspect of the present invention, there is provided a method for seismic retrofitting of an existing building by using a cast-in-place RC shear wall according to the first or second aspect, wherein an anchor bar is projected inward in advance along the inner surface of the beam-column frame. Disposing the steel frame material and bonding it to the beam-column frame, arranging the shear reinforcement of the earthquake-resistant wall inside the steel frame material, assembling a formwork for the wall, casting concrete, Dismantling the mold after curing.

According to a fifth aspect of the present invention, there is provided a method for seismic retrofitting of an existing building using the precast RC shear wall according to the first or second aspect, wherein a steel frame material is disposed at a peripheral portion along the inner surface of the column-beam frame. The method comprises the steps of: building a shear wall in the plane of a beam-column structure; and bonding the steel frame material of the wall to the inner surface of the beam-frame.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for reinforcing an existing building by using RC shear walls according to the first to fifth aspects of the present invention is a method for reinforcing an existing building by adding RC shear walls in the plane of a beam-column frame. It is preferably implemented as

Specifically, as shown in the embodiment in FIGS. 1 to 6, the length along the inner surface of the frame including the column 1 and the beam 2 is substantially equal to the inner dimension of the column 1 or the beam 2. (2 as an example
500mm x 5000mm) and the wall thickness W of the earthquake-resistant wall 3
A steel frame member 4 made of a grooved steel-like material having a considerably large size (typically about 180 mm) (for example, about 300 mm) is arranged in an inward direction, and is firmly fixed with a column-beam frame and an adhesive 5. The RC earthquake-resistant wall 3 having an anchor bar 6 projecting inward from the groove bottom of the steel frame member 4 is additionally provided to reinforce the steel frame member 4 (the invention according to claim 1).

However, the steel frame member 4 is arranged and bonded on the four circumferences of the earthquake-resistant wall 3 along the inner surfaces of the upper and lower beams 2 and 2 and the left and right columns 1 and 1 as shown in FIG. As described above, the method is roughly divided into a case where the upper and lower beams 2 and 2 are arranged only along the inner surfaces of the upper and lower beams, that is, only on the upper and lower sides of the earthquake-resistant wall 3 and bonded.

Further, the steel frame material 4 is not limited to a channel steel material. As long as the material has a flat surface large enough for strong adhesion to the column 1 and the beam 2, for example, a flat steel plate, a T-shaped steel, a hat-shaped steel, or another steel may be used in the same manner. (The invention according to claim 3).

The anchor bar 6 is generally stud-welded in consideration of the convenience of welding to the steel frame material 4, but in some cases, a reinforcing bar bent into a U-shape is formed in a wall length direction or a wall thickness direction. And welded and fixed.

In the groove of the steel frame member 4, a main reinforcing bar 7 is passed in the longitudinal direction, and a width stopping bar 8 is arranged to further enhance the restraining effect of the concrete. In the case where the steel frame material is not arranged along the inner surface of the column 1 as shown in FIG. 5, a structure in which the reinforcing cage 10 is arranged as shown in FIG. As described above, the outer peripheral portion of the RC earthquake-resistant wall 3 is made to have a wall thickness larger than the normal wall thickness W by utilizing the steel frame member 4 (FIG. 4), and the steel frame member 4 and the anchor bars 6 are further provided. Since the reinforcing bars 7, 8, and 10 are arranged to enhance the restraining effect of the concrete, there is no concern that local destruction will occur even if an excessive stress such as an earthquake is applied. In addition, since the steel frame member 4 and the beam-to-column frame are continuously and firmly bonded and integrated over the entire length, stress is reliably transmitted between the RC earthquake-resistant wall 3 and the beam-to-column frame, and seismic strengthening is performed. Is effective.

On the earthquake-resistant wall 3, double-walled shear reinforcements 9 are arranged. The outer peripheral portion of the RC earthquake-resistant wall 3 is restrained by a steel frame member 4. And the wall thickness of the peripheral part is the groove width dimension of the channel-shaped steel material which is larger than the original wall thickness W of the earthquake-resistant wall, and is inclined to the original wall thickness W (or a right-angled surface is possible). I'm connected.

Adhesive 5 for bonding steel frame material 4 to column and beam frame
For this, an epoxy resin is preferably used.

Next, FIGS. 7 to 10 show an embodiment of a method for reinforcing a seismic retrofit of an existing building by adding a cast-in-place RC shear wall according to the fourth aspect of the present invention. This RC
The earthquake-resistant wall 3 is an embodiment of a structure in which the steel frame members 4 and 4 are arranged only along the upper and lower beams 2 and 2.

First, FIGS. 7A and 7B show that a steel frame member 4 in which an anchor bar 6 is welded inward in advance and which is protruded is arranged along the inner surfaces of upper and lower beams 2 and 2 forming a beam-column frame. 5 shows the bonding stage. FIGS. 8A and 8B show that shear reinforcements 9 of the earthquake-resistant wall are arranged inside the upper and lower steel frame members 4 and 4 using the anchor bars 6, and the steel frame members are arranged along the inner surface of the column 1. Shows a stage in which a reinforcing bar cage 10 is arranged in place of the bar.
FIG. 9 shows a stage where the concrete formwork 11 for the wall is assembled and concrete is poured. 10A and 10B
Dismantles the formwork after curing the poured concrete
This shows the stage at which the addition of the C earthquake-resistant wall 3 has been completed.

Therefore, even if the existing finish is removed, there is no roughening or anchoring step, so that the degree of noise and vibration is extremely low, and the conditions under which the construction can be performed "as is" Can meet.

The method of reinforcing an existing building by adding a precast RC shear wall according to the fifth aspect of the present invention has been omitted up to illustrating the embodiment.
As can be easily understood from the embodiment of FIGS.
At a factory or the like, a precast concrete earthquake-resistant wall with a steel frame placed around the inner surface of the beam-column frame is manufactured, transported to the site and built into the beam-column frame, and the steel frame material around the wall is used. An adhesive is injected into the gap between the inner surface of the beam-column structure and firmly adhered. However, the precast concrete earthquake-resistant wall is built and built as a single plate that fits exactly in the plane of the beam-column structure. It is possible to selectively implement the case of completing a single plate-shaped earthquake-resistant wall.

[0025]

According to the first to fifth aspects of the present invention, the RC earthquake-resistant wall to be added by the method of reinforcing an existing building by the earthquake-resistant wall according to the first to fifth aspects of the present invention prevents the local destruction by restraining the outer peripheral portion with a steel frame material or the like. Because it is a structure, and the beam-column frame is a structure that firmly adheres through a steel frame material and reliably transmits excessive stress due to earthquakes etc. between them, it is a truly seismic element for seismic reinforcement of existing buildings Play an effect.

The seismic retrofitting method of the present invention does not involve roughening or anchoring, so that the degree of noise and vibration is extremely low, and satisfies the conditions that allow the construction to be performed "as is". Therefore, based on the necessity and recognition of seismic retrofitting of existing buildings designed according to the old standards, it is considered that this will greatly contribute to the spread of seismic retrofitting work.

[Brief description of the drawings]

FIG. 1 is a front view showing a state where an RC shear wall is added to an existing building by the method of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an enlarged sectional view showing the structure of the earthquake-resistant wall in detail from the same viewpoint as in FIG. 2;

FIG. 4 is a detailed sectional view taken along line 4-4 in FIG. 1;

FIG. 5 is a front view showing a state in which RC shear walls having different structures are added to an existing building by the method of the present invention.

FIG. 6 is a detailed sectional view taken along line 6-6 of FIG. 5;

FIGS. 7A and 7B are a front view and a vertical sectional view showing a stage in which a steel frame material is bonded to an existing building to add an RC shear wall by the method of the present invention.

FIGS. 8A and 8B are a front view and a longitudinal sectional view showing a stage where a shear reinforcement for a wall is arranged.

FIG. 9 is a longitudinal sectional view showing a stage in which a concrete formwork for a wall is assembled.

FIGS. 10A and 10B are a front view and a longitudinal sectional view showing a completed stage of an RC shear wall.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Column 2 Beam 3 RC earthquake-resistant wall 4 Steel frame material 5 Adhesive 6 Anchor bar 9 Shear reinforcement bar 7, 8, 10 Reinforcement bar at wall outer periphery

Continuing from the front page (72) Inventor Hidenori Hanamoto 8-21-1, Ginza, Chuo-ku, Tokyo Inside Takenaka Corporation Tokyo Main Store (72) Inventor Takahiro Moi 1-5-1, Otsuka, Inzai-shi, Chiba Pref. Takenaka Corporation Technical Research Institute (72) Inventor Yasumasa Miyauchi 1-5-1, Otsuka, Inzai City, Chiba Prefecture Inside Takenaka Corporation Technical Research Institute (72) Inventor Masahiko Fujimura 1-5-5 Otsuka, Inzai City, Chiba Prefecture 1 Takenaka Corporation Technical Research Institute Co., Ltd. (72) Inventor Masaru Fujimura 8-21-1, Ginza, Chuo-ku, Tokyo Inside Tokyo Headquarters Takenaka Corporation (72) Inventor Mitsuru Kimura Ginzahachi, Chuo-ku, Tokyo 21-2, Takenaka Corporation Tokyo Main Branch (72) Inventor Yuko Tsuji 8-21-1, Ginza, Ginza, Chuo-ku, Tokyo Inside Tokyo Main Branch, Takenaka Corporation (72) Inventor Toru Okuno Tokyo 8-21-1, Ginza, Chuo-ku, Tokyo Inside Takenaka Corporation Tokyo Main Store (72) Inventor Yasushi Sugiyama Capital Ginza, Chuo-ku eight-chome No. 21 No. 1 stock company Takenaka Corporation Tokyo head office within the F-term (reference) 2E125 AA04 AA14 AB12 AC01 AG58 BA13 BB02 CA81 EA25 2E176 AA04 BB13 BB28

Claims (5)

[Claims] An earthquake-resistant reinforcement method for an existing building in which an RC shear wall is added in the plane of a beam-and-column frame, wherein the length of the earthquake-resistant wall along the inner surface of the column-and-beam frame is substantially equal to the internal dimension of the column or beam. A steel frame material made of a grooved steel-like material having a considerably large thickness compared to the wall thickness, the groove shape is arranged inwardly and bonded to a beam-column frame, and the steel frame material is formed inwardly from the groove bottom of the steel frame material. A method of reinforcing existing buildings with RC shear walls, characterized by adding and reinforcing earthquake-resistant walls with anchor bars projecting therefrom. 2. The RC seismic resistance according to claim 1, wherein the steel frame members are arranged and adhered along the inner surfaces of the upper and lower beams or along the inner surfaces of the upper and lower beams and the right and left columns. A method of reinforcing an existing building with walls. 3. The RC shear wall according to claim 1, wherein the steel frame material is a flat steel plate having a flat adhesive surface, a T-shaped steel shape, or a hat-shaped steel material. Of existing buildings by seismic retrofit. 4. A step of arranging a steel frame member having an anchor bar projecting inward in advance along the inner surface of the column-beam frame and bonding the frame member to the column-beam frame, and shear-reinforcing a shear-resistant wall inside the steel frame member. The cast-in-place RC according to claim 1 or 2, comprising a step of arranging bars and a step of assembling a wall formwork, casting concrete, and dismantling the formwork after curing. A method of retrofitting an existing building with a shear wall. 5. A step of building a precast concrete earthquake-resistant wall having a steel frame material disposed in a peripheral portion along an inner surface of the column-beam frame in the plane of the column-beam frame, and applying the steel frame material of the earthquake-resistant wall to the column-beam frame. Characterized by comprising an inner surface and a step of bonding.
An earthquake-resistant reinforcement method for an existing building by the precast RC earthquake-resistant wall according to claim 1 or 2.