JPH09324543A - Reinforcing structure of existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcing structure capable of largely improving earthquake-resistant performance. SOLUTION: This reinforcing structure is constituted in such a manner that slits 15, 15... are formed to the earthquake-resisting wall 14 of an existing building 11 and fiber sheets 16 are stretched on both surfaces of the earthquake- resisting wall 14 while avoiding the slits 15. The fiber sheets 16 are composed of vertical sheets 16A and horizontal sheets 16B, vertical sheets 16A having fibers extended in the vertical direction are disposed to the sides of the slits 15, and horizontal sheets 16B consisting of fibers elongated in the horizontal direction are arranged to the upper and lower sections of the slits 15.

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 an existing building which is suitable for use in improving the earthquake resistance of an existing building, for example.

[0002]

2. Description of the Related Art Conventionally, in order to reinforce an existing building or the like, various methods such as arranging a reinforcing unit made of steel frame between the pillars and beams and arranging a reinforcing frame made of steel frame along the pillars and beams have been proposed. A reinforced structure is used.

When the building to be reinforced has a concrete wall such as an earthquake resistant wall, as one type of such a reinforcing structure, there is one side of the existing concrete wall 1 as shown in FIG. There is one that reinforces the concrete wall 1 by reinforcing the concrete 2 by reinforcing bars on both sides.

As another reinforcing structure, as shown in FIG. 8, there is a structure in which a fiber sheet 4 made of carbon fiber or the like is attached to the wall surface of the concrete wall 1.

[0005]

However, the conventional reinforcing structure for an existing building as described above has the following problems. First, as shown in FIG. 7, the reinforcement structure for additionally injecting concrete 2 into the concrete wall 1 is
Sometimes the weight is too great to apply. In addition, since the rigidity of the concrete wall 1 is improved as it is reinforced, the stress load on the concrete wall 1 is further increased, and as a result, the concrete wall 1 must be significantly reinforced. Then, when the deformation performance of the concrete wall 1 reinforced in this way and the frame 5 made of column beams do not match and an excessive horizontal external force is applied due to an earthquake or the like, the concrete wall 1 precedes the frame 5. Will collapse. As described above, it is difficult to effectively improve the seismic performance of the entire existing building with the reinforcement structure in which the concrete 2 is additionally overcast. In addition, noise and dust when placing the anchors 6 and roughening the concrete wall 1 also pose problems during construction. Further, since the concrete 2 is placed on the vertical surface, it is difficult to place the concrete 2 and there is also a problem that the surroundings become dirty.

Further, as shown in FIG. 8, in the reinforcing structure in which the fiber sheet 4 is attached to the concrete wall 1, the concrete wall 1 itself can be reinforced, but the frame 5 composed of the pillar beams around the concrete wall 1 can be reinforced. Since it cannot be achieved, slip failure (see FIG. 8B) occurs at the boundary between the concrete wall 1 and the frame 5 in the event of a large earthquake, etc., and it cannot be said that the structure is effective.

The present invention has been made in consideration of the above points, and it is an object of the present invention to provide a reinforcing structure for an existing building which can significantly improve the seismic performance.

[0008]

The invention according to claim 1 is
In order to reinforce the existing building, one or more slits extending in the vertical direction are formed on the concrete wall that constitutes the building, and the fiber sheet is attached to the concrete wall while avoiding the slits. It has a feature.

According to a second aspect of the present invention, in the reinforcing structure for an existing building according to the first aspect, the fiber sheet is one in which the extending direction of the fibers constituting the fiber sheet is the vertical direction. Is characterized by.

According to a third aspect of the present invention, in the reinforcing structure for an existing building according to the first aspect, the directions in which fibers constituting the fiber sheet extend are vertical and horizontal. Is used.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An example of an embodiment of a reinforcing structure for an existing building according to the present invention will be described below with reference to FIGS. In FIGS. 1 to 3, reference numeral 11 is an existing building made of, for example, a reinforced concrete frame structure, 12 is a pillar, 13 is a beam, and 14 is an earthquake resistant wall (concrete wall).

As shown in FIG. 1, in the structure after the existing building 11 is reinforced, the earthquake-resistant wall 14 has slits 15, 15, ... Which extend in the vertical direction at predetermined horizontal intervals.
Are formed. Each slit 15 is formed such that its upper end portion and lower end portion are located apart from the upper and lower beams 13, 13 by a predetermined dimension.

Fiber sheets 16 are attached to both sides of the earthquake-resistant wall 14 with an adhesive or the like. The fiber sheet 16 includes a vertical sheet 16A attached so as to extend in the vertical direction, and a horizontal sheet 1 extending in the horizontal direction.
6B and. Each longitudinal sheet 16A is
It is stuck between the slits 15 and 15 adjacent to each other. Each lateral sheet 16B is attached between the beam 13 and the lower ends of the slits 15, 15, .... In this way, the fiber sheet 16 is attached to the earthquake-resistant wall 14 while avoiding the slits 15, 15, ....

The fiber sheet 16 is made of, for example, carbon fiber, aramid fiber, glass fiber or the like, and its fiber direction is such that the vertical sheet 16A is vertical and the horizontal sheet 16B is horizontal. It is set.

In the reinforced structure of the earthquake-resistant wall 14 of the existing building 11 having the above-described structure, the earthquake-resistant wall 14 has a middle portion 14A in which slits 15, 15, ... Therefore, the proof stress is lower than the so-called one-piece upper 14B and lower 14C.

To apply the above-mentioned reinforcing structure to the existing building 11,
First, as shown in FIG. 2, using a high-pressure water, a diamond cutter, or the like, slits 15,
.. are formed. Then, each slit 15 is filled with a sealing material (not shown) having elasticity for rust prevention. Next, as shown in FIG. 1, the vertical sheet 16A and the horizontal sheet 16B may be attached to predetermined positions of the earthquake-resistant wall 14 with an adhesive or the like.

In the existing building 11 which is reinforced by applying such a reinforcing structure, when an excessive external force is input due to an earthquake or the like, the horizontal load thereof first causes the space between the fiber sheets 16 and 16. Middle part 1 of the seismic wall 14 sandwiched
4A tries to yield in advance from around the slits 15, 15, .... However, the seismic wall 14 is a fiber sheet 16,
Since it is sandwiched between the sixteen, even after the reinforcing bars in the concrete have yielded, the fibers that make up the fiber sheet 16 suppress the elongation in the extending direction, thereby restraining the displacement of the seismic wall 14. , Maintain proof stress. Therefore, the earthquake-resistant wall 14 has a form similar to that of being filled between the fiber sheets 16 and 16, and deformation and buckling are suppressed.

More specifically, when the seismic wall 14 yields in advance, as shown in FIG.
The crack C1 is likely to occur from the corner portion of No. 5. In this portion, the longitudinal sheet 16A and the transverse sheet 16B are overlapped with each other, and the fibers are present in two directions, the longitudinal direction and the lateral direction. Therefore, the corner portions of the slit 15 are constrained in two directions. The crack C1 is prevented from being generated and increased.

Further, as shown in FIG. 3 (b), the seismic wall 1
When a bending stress is applied to 4, cracks C2 in a substantially horizontal direction are likely to occur on the side of the slit 15, but in this portion, the fibers in the vertical direction of the vertical sheet 16A work,
As a result, reinforcement against bending can be achieved.

The seismic wall 14 is made of a fiber sheet 16
As a result, its toughness is improved and becomes tenacious. Here, in FIG. 4, the line indicated by the symbol a indicates the deformation performance of the earthquake resistant wall 14, and the line indicated by the symbol b indicates the deformation performance of the conventional earthquake resistant wall.

In the reinforcing structure of the existing building 11 described above, the earthquake-resistant wall 14 is provided with slits 15, 15, ... And the fiber sheet 16 is stretched on both sides of the earthquake-resistant wall 14 while avoiding the slit 15. Has become. Further, the fiber sheet 16 is composed of a vertical sheet 16A and a horizontal sheet 16B, and a vertical sheet 16A having fibers extending in the vertical direction is disposed on the side of the slit 15 and is provided above and below the slit 15. In this configuration, a lateral sheet 16B made of fibers extending in the lateral direction is arranged. By thus extending the fiber sheet 16 on the earthquake-resistant wall 14 of the existing building 11, when the earthquake-resistant wall 14 is about to be deformed by an external force, the fibers forming the fiber sheet 16 cause the fiber sheet 16 to extend in the extending direction. Of the seismic wall 14 can be restrained and the yield strength can be secured. Therefore, the earthquake resistance of the existing building 11 can be effectively improved. When the existing building 11 is to be reinforced in this way, noises, dust, dirt, etc. are generated because it is sufficient to simply attach the fiber sheet 16 to the seismic wall 14 after forming the slit 15 in the construction. It can be done easily and in a short period of time.

Moreover, the slit 1 is formed in the existing earthquake-resistant wall 14.
By forming 5, 15, ..., the rigidity of the central portion 14A of the earthquake-resistant wall 14 can be set lower than other portions, and when an excessive horizontal load is applied due to an earthquake or the like,
From this part, the earthquake resistant wall 14A will be yielded in advance.
By appropriately setting the intervals and lengths of the slits 15 as described above, it is possible to control the stress / deformation of the earthquake-resistant wall 14 after reinforcement, and the earthquake-resistant wall 14 and the frame including the columns 12 and the beams 13 can be controlled. The balance can be set optimally, and as a result, the seismic resistance of the existing building can be improved more effectively.

In the above-mentioned embodiment, the reinforcement by the fiber sheet 16 is applied to all the earthquake-resistant walls 14 of the existing building 11.
Alternatively, it may be applied to a part of the seismic wall 14, for example, only the core part of the existing building 11 or only the outer peripheral part. It goes without saying that not only the earthquake resistant wall 14 but also a normal concrete wall can be reinforced in the same manner. Further, the slits 15 formed in the earthquake-resistant wall 14 are not limited to the intervals and lengths thereof, and may be appropriately set to adjust the rigidity of the reinforced earthquake-resistant wall 14.

Further, the longitudinal sheet 16A and the transverse sheet 16B of the fiber sheet 16 to be attached to the seismic wall 14 are made of fibers extending in one direction, respectively.
You may make it comprise from the fiber of two directions which mutually orthogonally cross. In this case, when shear stress acts on the earthquake-resistant wall 14, cracks are liable to be obliquely generated laterally of the slit 15, but bidirectional fibers work in this portion, thereby effectively reinforcing shearing. Can be planned. Further, the fiber sheet 16 is composed of the vertical sheet 16A and the horizontal sheet 16B, and as shown in FIG. 5, one fiber sheet 16 'is attached to the entire surface of the earthquake-resistant wall 14. It may be configured. Also in this case, in order to allow the displacement of the seismic wall 14 on both sides of the slit 15, an adhesive or the like for attaching the fiber sheet 16 ′ is applied avoiding the slit 15. Also, if you want to further strengthen,
As shown in FIG. 6, the fibrous sheet 16 ″ is provided with slits 15,
It is good also as a structure wound around the whole circumference of the earthquake-resistant wall 14 between 15.

Of course, the material of the fibers forming the fiber sheet 16 may be appropriately selected according to the required degree of reinforcement, and materials other than those mentioned above may be adopted.

In addition, the slit 15 is filled with a sealing material having elasticity, but this does not matter as long as it allows displacement of the seismic wall 14 on both sides of the slit 15, regardless of its material. For example, other than this, poorly mixed mortar or the like may be used.

[0027]

As described above, according to the reinforcing structure for an existing building according to claim 1, one or more slits extending in the vertical direction are formed in the concrete wall constituting the existing building, and the fiber sheet is formed. The structure is such that it is attached to the concrete wall surface while avoiding the slits. Further, according to the existing building reinforcement structure of the second aspect, the extending direction of the fibers forming the fiber sheet is the vertical direction. Also,
According to the reinforcing structure of the existing building of claim 3, the fibers that form the fiber sheet are extended in two directions, that is, the vertical direction and the horizontal direction. By attaching the fiber sheet to the existing concrete wall surface in this way, when the concrete is about to be deformed, the fibers constituting the fiber sheet suppress the extension in the extending direction, and thereby the existing building is constructed. The earthquake resistance of can be improved. Moreover, by forming a slit in the existing concrete wall, the rigidity of this part of the concrete wall can be set lower than other parts, and the slit is formed when an excessive horizontal load is applied due to an earthquake or the like. It is possible to pre-yield from part of the concrete wall. By appropriately setting the intervals and lengths of such slits, it becomes possible to control the stress and deformation of the concrete wall and set the balance between the concrete wall and the frame optimally. The earthquake resistance of can be improved more effectively. In addition, when reinforcing an existing building using such a reinforcing structure, it is sufficient to simply attach a fiber sheet after forming a slit in a concrete wall, so noise, dust, dirt, etc. are generated during the construction. Without doing, it can be done easily and in a short period of time.

[Brief description of drawings]

FIG. 1 is an elevational view showing an example of a reinforcing structure for an existing building according to the present invention.

FIG. 2 is a view showing a construction method when reinforcing the existing building by applying the reinforcing structure, and is an elevation view showing a state in which a slit is formed in a concrete wall constituting the building.

FIG. 3 is an elevational view showing a part of the concrete wall when an external force such as an earthquake acts.

FIG. 4 is a diagram showing the deformation performance of the concrete wall.

FIG. 5 is an elevation view showing another example of the reinforcing structure for an existing building according to the present invention.

FIG. 6 is an elevational view showing still another example of the reinforcing structure for an existing building according to the present invention.

FIG. 7 is a side sectional view showing an example of a conventional reinforcing structure for an existing building.

FIG. 8 is a side cross-sectional view showing another example of a conventional reinforcing structure for an existing building and a diagram showing the deformability of a concrete wall to which the structure is applied.

[Explanation of symbols]

 11 Existing Building 14 Seismic Wall (Concrete Wall) 15 Slit 16 Fiber Sheet

Claims (3)

[Claims] 1. In order to reinforce an existing building, one or more slits extending vertically are formed in a concrete wall constituting the building, and a fiber sheet is attached to the concrete wall surface while avoiding the slit. Reinforcement structure of existing building characterized by being. 2. The reinforcing structure for an existing building according to claim 1, wherein the fiber sheet is one in which the extending directions of the fibers constituting the fiber sheet are vertical. Reinforcement structure. 3. The reinforcing structure for an existing building according to claim 1, wherein the fiber sheet has two extending directions, namely, a vertical direction and a horizontal direction. Reinforcement structure of existing building characterized by.