JP2022076425A - Reinforcement structure of existing structure - Google Patents

Abstract

To provide a reinforcement structure of an existing structure capable of reinforcing the existing structure without changing an external appearance of the existing structure.SOLUTION: A reinforcement structure 1 for reinforcing a wall 12 of an existing structure 10 comprises a fiber layer 20 provided on a surface of the wall 12, a steel plate 30 bonded on the fiber layer 20 with an adhesive agent and a post-construction anchor 40 for fixing the steel plate 30 to the wall 12. According to the invention, the existing structure 10 can be reinforced without changing an external appearance of the existing structure 10 as the fiber layer 20 and the steel plate 30 are provided on the wall 12 which is an inside skeleton.SELECTED DRAWING: Figure 4

Description

The present invention relates to a reinforcing structure for seismic retrofitting on the internal skeleton side of an existing structure.

Conventionally, seismic retrofitting of existing structures has been performed (see Patent Documents 1 to 3).
Patent Document 1 discloses a structure for reinforcing an existing tubular structure. Specifically, this reinforcing structure includes a flat bar which is a linear bending reinforcing material arranged in the cylindrical axial direction along the inner wall surface of the tubular structure, and the upper surface of the flat bar and the inside of the tubular structure. It is provided with a polyurea resin as a film-like reinforcing coating material provided over the wall surface.
Patent Document 2 shows a fiber-reinforced resin film provided on the surface of a concrete skeleton. The fiber-reinforced resin film has a carbon fiber sheet and a resin that has been impregnated and cured by the carbon fiber sheet.
Patent Document 3 discloses a reinforcing method in which an existing column is surrounded by a reinforcing cylinder and a curing agent is injected into the inside of the reinforcing cylinder. The reinforcing cylinder is composed of a combination of a plurality of divided reinforcing frames, and the reinforcing frame is composed of an inner shear reinforcing iron plate and an outer concrete plate.

Japanese Unexamined Patent Publication No. 2020-105733 Japanese Unexamined Patent Publication No. 2013-245432 Japanese Patent No. 3755115

An object of the present invention is to provide a reinforcing structure of an existing structure capable of reinforcing the existing structure without changing the appearance of the existing structure by reinforcing the internal skeleton side of the existing structure.

As a reinforcing structure of an existing structure, the present inventors provide a fiber layer by pasting a carbon fiber sheet or an aramid fiber sheet on the surface of an internal frame, and a steel plate is pasted on the fiber layer, and further. By penetrating the anchor member from above this steel plate and fixing it to the internal skeleton, the internal space can be reduced as much as possible without changing the appearance of the existing structure compared to the case where concrete is added to the inner skeleton side. The present invention was made by focusing on the point that the shear strength can be improved and the seismic performance of the existing structure can be improved while reducing the amount.
The reinforcing structure of the first invention (for example, the reinforcing structures 1 and 1B described later) is a structure for reinforcing the internal frame (for example, the wall 12 described later) of the existing structure (for example, the existing building 10 described later). , A fiber layer provided on the surface of the internal frame (for example, the fiber layer 20 described later) and a steel plate bonded on the fiber layer with an adhesive (for example, an adhesive 31 described later) (for example, described later). It is characterized by including a steel plate 30) and an anchor member (for example, a post-installed anchor 40 described later) for fixing the steel plate to the internal frame.

According to the present invention, a fiber layer is provided on the inner skeleton, a steel plate is adhered on the fiber layer with an adhesive, and the steel plate is further fixed to the inner skeleton with an anchor member. As a result, the existing structure can be reinforced without changing the appearance of the existing structure.
Further, by adopting a steel plate having excellent strength, the steel plate can be made thinner, so that the reduction of the internal space can be minimized as compared with the case where a concrete skeleton is added to the surface of the internal skeleton as seismic reinforcement.
Further, since the fiber layer is sandwiched between the inner skeleton and the steel plate, twisting of the fiber layer can be suppressed as compared with the case where only the fiber layer is provided on the surface of the inner skeleton.

In the reinforcing structure of the second invention, the steel plates are rectangular plates, and a plurality of the steel plates are arranged side by side in the horizontal direction and a plurality of stages are arranged vertically, and vertical joints (for example) between the steel plates in each stage are arranged. , The vertical joints 32) described later are characterized in that they are arranged at positions different from the vertical joints in the upper and lower stages.

According to the present invention, the vertical joints between the steel plates of each stage are set at different positions from the vertical joints of the upper and lower stages. That is, the vertical joints of the steel plate were used as horse joints. The vertical joints tend to be fragile parts, but since these vertical joints are used as horse joints, the reinforcing effect of the steel plate is reduced compared to the case where the vertical joints are provided at the same positions as the vertical joints in the upper and lower stages. The shear strength can be improved without any problem.

In the reinforcing structure of the third invention, the internal skeleton is a wall provided above and below the floor slab (for example, the floor slab 14 described later), and the fiber layer penetrates the floor slab and is above and below the floor slab. It is characterized by being continuously provided on the wall.

According to the present invention, since the fiber layer is continuously provided on the upper and lower walls through the floor slab, a long fixing section (fixing length) of the fiber layer can be secured. Seismic reinforcement can be done by integrating the walls.

The reinforcing structure of the fourth invention (for example, the reinforcing structure 1A described later) is a structure for reinforcing the internal skeleton (for example, the wall 12 described later) of the existing structure (for example, the existing building 10 described later), and is described above. A steel plate (for example, a steel plate 30 described later) bonded to the surface of the internal skeleton with an adhesive (for example, an adhesive 31 described later) and an anchor member (for example, a post-construction anchor described later) for fixing the steel plate to the internal skeleton. 40), and the steel plate is in the shape of a rectangular plate, and is arranged side by side in the horizontal direction and is arranged in a plurality of stages vertically, and vertical joints between the steel plates in each stage (for example, described later). The vertical joint 32) is characterized in that it is arranged at a position different from that of the upper and lower vertical joints.

According to the present invention, since the steel plate is adhered on the inner skeleton with an adhesive and the steel plate is fixed to the inner skeleton with an anchor member, the existing structure can be reinforced without changing the appearance of the existing structure. ..
In addition, by adopting a steel plate with excellent strength, the steel plate installed on the internal skeleton can be made thinner, so the reduction in internal space is as small as possible compared to the case where a concrete skeleton is added to the surface of the internal skeleton as seismic reinforcement. can.

According to the present invention, by reinforcing the internal skeleton side of the existing structure, it is possible to provide a reinforcing structure of the existing structure capable of reinforcing the existing structure without changing the appearance of the existing structure.

It is a vertical sectional view of the existing building to which the reinforcing structure which concerns on 1st Embodiment of this invention is applied. It is a top view of the core part of the existing building which concerns on 1st Embodiment. It is a schematic plan view of the reinforcement structure which concerns on 1st Embodiment. It is an arrow view (front view) of AA of the reinforcement structure of FIG. It is BB sectional view of the reinforcement structure of FIG. It is sectional drawing of the joint part of the wall and the floor slab of the reinforcing structure which concerns on 1st Embodiment. It is a flowchart of the construction procedure of the reinforcement structure which concerns on 1st Embodiment. It is a vertical sectional view of the reinforcement structure which concerns on 2nd Embodiment of this invention. It is a front view of the reinforcement structure which concerns on 3rd Embodiment of this invention.

The present invention is a reinforcing structure that reinforces the internal skeleton side of an existing structure without changing the appearance of the existing structure. Specifically, a carbon fiber sheet or an aramid fiber sheet is attached to the surface of the internal frame of an existing structure using an adhesive to provide a fiber layer, and then a steel plate is provided on the surface of the fiber layer. This is a reinforcing structure of an existing structure in which an anchor member is penetrated from the outside of this steel plate and fixed to the internal frame.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the following embodiments, the same components will be designated by the same reference numerals, and the description thereof will be omitted or simplified.
[First Embodiment]
FIG. 1 is a vertical sectional view of an existing building 10 as an existing structure to which the reinforcing structure 1 according to the first embodiment of the present invention is applied. FIG. 2 is a plan view of the first floor portion of the core portion 11 of the existing building 10.

The existing building 10 is a reinforced concrete building, and a columnar core portion 11 extending in the vertical direction is provided in the central portion of the existing building 10.
The core portion 11 includes a cylindrical reinforced concrete wall 12 as an internal frame, an elevator shaft 13 provided inside the wall 12, a floor slab 14 on each floor, and stairs 15.
Inside the elevator shaft 13, an elevator 16 that moves up and down is housed, and the floor slab 14 on each floor serves as an elevator hall or an office space.

The reinforcing structure 1 of the present invention seismically retrofits the wall 12 constituting the core portion 11 of the existing building 10.
FIG. 3 is a schematic plan view of the reinforcing structure 1. FIG. 4 is an arrow view (front view) of AA of the reinforcing structure 1 of FIG. FIG. 5 is a cross-sectional view taken along the line BB of the reinforcing structure 1 of FIG.
The reinforcing structure 1 comprises a fiber layer 20 provided on the inner wall surface of the wall 12, a plurality of steel plates 30 bonded on the fiber layer 20 with an adhesive 31 (for example, an epoxy resin adhesive), and a steel plate 30. A post-installed anchor 40 as an anchor member to be fixed to the wall 12 is provided.

The fiber layer 20 is configured by horizontally attaching a plurality of carbon fiber sheets 21 having a predetermined width extending in the vertical direction to the inner wall surface of the wall 12. Specifically, using an epoxy resin adhesive or a methacrylate adhesive, the carbon fiber sheet 21 is stretched vertically from the lower end to the upper end of the wall 12 and attached, and this work is performed on the inner wall surface of the wall 12. By repeating in the horizontal direction along the wall 12, the fiber layer 20 is formed on the surface of the wall 12.
Further, the fiber layer 20 is attached to the wall 12 over a plurality of floors from the first basement floor to the upper floor of the existing building 10. The fiber layer 20 is provided as a load bearing material in the horizontal direction of the wall 12, and a required amount is provided mainly for the purpose of improving the shear strength of the wall 12.
The fiber layer 20 is not limited to the carbon fiber sheet, and may be formed by using an aramid fiber sheet.

As shown in FIG. 6, the walls 12 are arranged above and below the floor slab 14, and through holes 17 are formed in the floor slab 14 at predetermined intervals along the inner wall surface of the wall 12. A part of the carbon fiber sheet 21 is bundled and inserted into the through hole 17 of the floor slab 14, and the upper side of the carbon fiber sheet 21 is attached to the upper wall 12 of the floor slab 14, and is under the carbon fiber sheet 21. The side is attached to the lower wall 12 of the floor slab 14. As a result, the carbon fiber sheet 21 is continuously provided on the upper and lower walls 12 of the floor slab 14. Further, at the upper and lower ends of the carbon fiber sheet 21, the bundled carbon fiber sheets 21 are spread out in a fan shape and attached to the wall 12 in order to increase the adhesive strength between the surface of the wall 12 and the carbon fiber sheet 21. ing.

The steel plate 30 has a rectangular plate shape and is provided on the first floor of the existing building 10. As shown in FIG. 4, the steel plates 30 are arranged side by side in the horizontal direction when the inner wall surface of the wall 12 is viewed from the front, and are arranged in a plurality of stages vertically. As the steel plate 30, a structural steel plate having a thickness of 9 mm to 16 mm is preferable because it can be in close contact with the surface of the wall 12 and in consideration of work efficiency in reinforcement work. In addition, the thickness of the fiber layer 20, the steel plate 30, and the post-installed anchor 40 (that is, the dimension from the surface of the wall 12 to the nut portion of the post-installed anchor 40) secures the internal space of the existing building 10 as wide as possible by seismic reinforcement. It was set to about 50 mm so that it could be used.
Further, the steel plate 30 is a horse joint. That is, the vertical joints 32 between the steel plates 30 in each stage are arranged at different positions from the vertical joints 32 in the upper and lower stages.

The steel plates 30 are attached to the fiber layer 20 side by side in the horizontal direction using an adhesive 31. Like the fiber layer 20, the steel plate 30 is provided as a load bearing material in the horizontal direction of the wall 12, and a required amount is provided mainly for the purpose of improving the shear strength of the wall 12.
The post-installed anchor 40 includes an anchor bolt 41 that penetrates the steel plate 30 and the fiber layer 20 and is driven into the wall 12, and a nut 42 that is screwed into the anchor bolt 41 and presses the steel plate 30 from above.

The construction procedure of the above reinforcing structure 1 will be described with reference to the flowchart of FIG.
In step S1, the fiber layer 20 is formed on the inner wall surface of the wall 12. Specifically, the carbon fiber sheet 21 having a predetermined width is attached in the vertical direction from the lower end to the upper end of the wall 12 with an adhesive. By repeating this operation in the horizontal direction along the inner wall surface of the wall 12, a plurality of carbon fiber sheets 21 having a predetermined width are attached in the horizontal direction to form the fiber layer 20.

In step S2, the steel plate 30 is attached on the fiber layer 20. Specifically, a plurality of rectangular plate-shaped steel plates 30 are attached side by side in the horizontal direction with an adhesive 31, and a plurality of plates are attached vertically.
In step S3, the post-installed anchor 40 is installed from above the steel plate 30. Specifically, a through hole is formed in the steel plate 30 and the fiber layer 20 from above the steel plate 30 with a drill or the like, an anchor bolt 41 is driven into the through hole, and a nut 42 is screwed into the anchor bolt 41 and tightened.

According to this embodiment, there are the following effects.
(1) A fiber layer 20 was provided on a reinforced concrete wall 12, a steel plate 30 was adhered onto the fiber layer 20 with an adhesive 31, and the steel plate 30 was further fixed to the wall 12 with post-installed anchors 40. .. As a result, the existing building 10 can be reinforced without changing the appearance of the existing building 10.
Further, since the steel plate 30 can be made thinner by adopting the steel plate 30 having excellent strength, the reduction of the internal space is minimized as compared with the case where the concrete skeleton is added to the surface of the wall for seismic reinforcement, and the wall 12 is used. Can be reinforced.
Further, by fixing the steel plate 30 to the wall 12 with post-installed anchors 40, it is possible to prevent the steel plate 30 attached along the wall 12 from being deformed in the out-of-plane direction and maintain the shape of the steel plate 30.

(2) Since the fiber layer 20 is sandwiched between the wall 12 and the steel plate 30, the fiber layer 20 and the steel plate 30 are integrated with the wall 12, and the fiber layer 20 is twisted as compared with the case where only the fiber layer is provided on the surface of the wall 12. Can be suppressed. Therefore, the shear strength of the wall 12 which is the internal frame can be reinforced.
Further, a fiber layer 20 is provided on the surface of the wall 12 which is an internal frame, a steel plate 30 is attached on the fiber layer 20, and the fiber layer 20 and the steel plate 30 are fixed to the wall 12 with post-installed anchors 40. Even when not only the tensile force but also the compressive force acts on the fiber layer 20, the fiber layer 20 can be prevented from twisting.

(3) The vertical joints 32 of the steel plates 30 of each stage are set at different positions from the vertical joints 32 of the upper and lower stages. That is, the vertical joint 32 of the steel plate 30 was used as the horse joint. Therefore, the shear strength can be improved without lowering the reinforcing effect of the steel sheet 30 as compared with the case where the vertical joints of the steel sheet are the potato joints.
(4) Since the carbon fiber sheets 21 are arranged side by side in the horizontal direction to form the fiber layer 20, the shear strength of the wall 12 can be improved without changing the bending strength of the wall 12.
(5) By bundling the carbon fiber sheets 21 of the fiber layer 20 and inserting them into the through holes 17 of the floor slab 14, the carbon fiber sheets 21 are continuously provided on the upper and lower walls 12, so that the fiber layer 20 is fixed. Since a long section (fixing length) can be secured, the upper and lower walls 12 sandwiching the floor slab 14 can be integrally reinforced against earthquakes.

[Second Embodiment]
FIG. 8 is a vertical sectional view of the reinforcing structure 1A according to the second embodiment of the present invention.
The present embodiment is different from the first embodiment in that the fiber layer 20 is not provided and the steel plate 30 is directly bonded to the wall 12 with the adhesive 31.
According to this embodiment, there is the same effect as the above-mentioned (1) and (3).

[Third Embodiment]
FIG. 9 is a front view of the reinforcing structure 1B according to the third embodiment of the present invention.
In the present embodiment, the fiber layer 20 is different from the first embodiment in that the fiber layer 20 is formed by sticking a plurality of horizontally extending carbon fiber sheets 21 having a predetermined width on the inner wall surface of the wall 12 in the vertical direction.
According to this embodiment, there is the same effect as the above-mentioned (1) to (4).

The present invention is not limited to the above-described embodiment, and modifications, improvements, and the like to the extent that the object of the present invention can be achieved are included in the present invention.
For example, in each of the above-described embodiments, the post-installed anchor 40 is installed on the steel plate 30, but the present invention is not limited to this. That is, after the fiber layer 20 is attached to the inner wall surface of the wall 12, holes are drilled in the wall 12 from above the fiber layer 20 for post-installed anchors 40, and the post-installed anchors 40 are installed. Next, a steel plate having through holes for post-installed anchors 40 may be attached onto the fiber layer 20.
Further, in each of the above-described embodiments, the upper and lower steel plates 30 are provided so as to be in contact with each other, but the present invention is not limited to this, and the upper and lower steel plates may be provided at predetermined intervals.

1, 1A, 1B ... Reinforcing structure 10 ... Existing building (existing structure) 11 ... Core part 12 ... Wall (internal frame) 13 ... Elevator shaft 14 ... Floor slab 15 ... Stairs 16 ... Elevator 17 ... Through hole 20 ... Fiber layer 21 ... Carbon fiber sheet 30 ... Steel plate 31 ... Adhesive 32 ... Vertical joint 40 ... Post-installed anchor (anchor member) 41 ... Anchor bolt 42 ... Nut

Claims (3)

It is a structure that reinforces the internal frame of the existing structure.
The fiber layer provided on the surface of the internal frame and
A steel plate bonded on the fiber layer with an adhesive and
A reinforcing structure of an existing structure, comprising: an anchor member for fixing the steel plate to the internal frame. The steel plate has a rectangular plate shape, is arranged side by side in the horizontal direction, and is arranged in a plurality of stages vertically.
The reinforcing structure of an existing structure according to claim 1, wherein the vertical joints between the steel plates in each stage are arranged at positions different from the vertical joints in the upper and lower stages. It is a structure that reinforces the internal frame of the existing structure.
A steel plate bonded to the surface of the internal frame with an adhesive,
An anchor member for fixing the steel plate to the internal frame is provided.
The steel plate has a rectangular plate shape, is arranged side by side in the horizontal direction, and is arranged in a plurality of stages vertically.
A reinforcing structure of an existing structure, wherein the vertical joints between the steel plates in each stage are arranged at positions different from the vertical joints in the upper and lower stages.

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