JP2017115437A - Reinforcement method for building structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcement method capable of achieving well-balanced improvement of strength as that for a building structure by making reinforcement columns function effectively while reducing the number of the reinforcement columns.SOLUTION: A reinforcement method for an existing building structure including a plurality of existing columns includes the steps of: on the basis of particularity of the existing building structure, classifying the plurality of existing columns A into main columns A for receiving force acting on other columns in cooperation with the other columns and sub columns A composed of the other columns A; identifying a column to be reinforced of the main columns A as a reinforcement necessary main column A; identifying a beam for directly or indirectly transmitting force received by the sub columns A to the reinforcement necessary main column A as a reinforcement necessary beam B; and reinforcing the reinforcement necessary main column A and the reinforcement necessary beam B.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method for reinforcing an existing building.

Existing columns may be reinforced for seismic reinforcement of existing buildings.
Normally, the strength of pillars in buildings has been reviewed, and for example, pillars in places where loads are applied and pillars that require severe deterioration are identified, and all of them have been reinforced.
As a column reinforcing method, for example, as shown in FIG. 8, the entire circumference of the existing column 1 is surrounded by a reinforcing frame 2 while maintaining an interval, and the axial streak 3 is disposed within the interval and a grout material is used. A reinforcing layer is formed around the existing pillar 1 by filling the filler 4 such as.

The reinforcing frame 2 is configured by overlapping the end portions of four steel plates 5 having an L-shaped cross section, and the axial length thereof is set to a plurality of lengths of the reinforcement target portions of the existing columns 1. The length is divided. Such a reinforcing frame 2 is laminated along the existing pillar 1 so as to cover the reinforcement target portion of the existing pillar 1.
At the intersection between the existing pillar 1 and the beam, a reinforcing frame for a crossing portion having a U-shaped or L-shaped cross section (not shown) is stacked on the reinforcing frame 2 and the reinforcing frame for the crossing portion is stacked. The inside of the body is filled with the filler 4 to form a reinforcing layer together with the reinforcing frame 2.
Further, a belt-like sheet 6 made of fiber or the like is bonded to the outer periphery of the reinforcing frame 2 and the reinforcing frame for the intersection (see Patent Document 1).

JP 2008-240368 A JP 2011-026786 A

As described above, in the conventional reinforcing method in which all the columns that need reinforcement are reinforced, the larger the number of columns that need reinforcement, the larger the construction becomes. In addition, there is a problem that the cost increases due to the time required.
Moreover, since the reinforcement layer is provided in the existing pillar 1, the post-reinforcement pillar becomes thick, and if there are many such thick pillars, there is a problem that the living space becomes narrow.
However, if the pillars to be reinforced are left as they are, the reinforcement effect cannot be increased sufficiently, and not only the unreinforced pillars are broken, but the balance of the entire structure is lost, and Strength cannot be maintained.
The objective of this invention is providing the reinforcement method which can improve the intensity | strength as a building in a well-balanced manner that the reinforced column functions effectively, reducing the number of columns to reinforce.

  1st invention is the reinforcement method of the existing building provided with several existing pillars, Comprising: The force which acts on other pillars other than said several existing pillars based on the special property of the said existing building Categorizing the main pillar in cooperation with other pillars and the secondary pillars composed of the other pillars, identifying the pillars to be reinforced among the main pillars as the main pillars requiring reinforcement, A step of specifying a beam for transmitting the force received by the column directly or indirectly to the main column requiring reinforcement as a beam requiring reinforcement, and a step of reinforcing the main column requiring reinforcement and the beam requiring reinforcement It is characterized by.

  The second invention is characterized by comprising a step of specifying a column to be reinforced among the sub-pillars as a reinforcing sub-column, and a step of reinforcing the reinforcing sub-column.

According to 1st invention, the force which acts on a follower pillar can be transmitted to the reinforced main pillar requiring reinforcement via the reinforced main beam required. For this reason, the main pillar shares the seismic force acting on the follower pillar, and even if there is a follower pillar that is not reinforced, the pillar can be prevented from being destroyed.
Even if a non-reinforcing follower pillar is destroyed, the beam intersecting with the follower pillar is reinforced and the function as a beam is maintained, so that the entire structure of the building can be maintained.
As described above, according to the present invention, the strength of the entire building can be maintained in a well-balanced manner without reinforcing all the columns. As a result, the time required for the reinforcement work can be shortened and the construction cost can be reduced.
Further, even if the pillars are thickened by reinforcement, the number of pillars that are thickened can be reduced, so that the living space can be maintained.

According to the second aspect, the strength of the follower can be increased.
Since the follower column is a column that imparts force to the main column requiring reinforcement, the reinforcement of the follower column is simpler than the reinforcement of the main column. Therefore, the reinforcement of the follower pillar can make the living space not so narrow. In addition, since simple reinforcement is sufficient, the reinforcement work can be simplified and the increase in cost can be suppressed.

It is the schematic diagram which showed arrangement | positioning of the pillar and beam of the building to which the reinforcement method of embodiment is applied. It is the schematic diagram which showed arrangement | positioning of the main pillar requiring reinforcement and the reinforcement beam required in the reinforcement method of embodiment. It is a perspective view which shows the reinforcement example of the main pillar required for reinforcement along a wall, and a reinforcement beam. It is sectional drawing of the example of a reinforcement shown in FIG. It is the VV sectional view taken on the line of FIG. It is sectional drawing which shows the example of reinforcement of the main pillar required reinforcement located in the center of a room. It is the VII-VII sectional view taken on the line of FIG. It is sectional drawing which shows the reinforcement structure of the existing pillar of a prior art example.

An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows the arrangement of pillars A1 to A18 and beams B1 to B27 of an existing building to which the reinforcing method of the present invention is applied. In FIG. 1, all the pillars A1 to A18 are schematically shown by black squares or white squares, and the beams B1 to B27 between the pillars are schematically shown by bold lines. In the following description, when there is no particular need to specify the position, the description will be made using the symbol A with the numerals omitted and the symbol B as the beam.
Further, it is assumed that a wall 7 (see FIG. 3) is provided below the beam B constituting the contour of the figure shown in FIG.

The procedure for reinforcing the building shown in FIG. 1 is as follows.
First, all the pillars A1 to A18 are classified into main pillars and secondary pillars. The main pillar is a pillar that receives the power received by other pillars in cooperation with the pillar. Therefore, it is a pillar that requires relatively high yield strength.
On the other hand, the follower column is a column that transmits a force acting on itself to the main column A via the beam B and gives the main column A a force.

Which of the all pillars A is the main pillar and which is the secondary pillar is determined based on the special characteristics of the existing building. For example, it is determined in consideration of the degree of deterioration of the column due to changes over time of the entire building, how to apply the load, and the like.
In this embodiment, the pillar A indicated by a black square in FIG. That is, the pillars A1, A3, A5, A7, A11, A16, and A18 are main pillars. The other pillars are secondary pillars.

Next, among the main pillars A, the main pillars to be reinforced are specified. Whether or not to reinforce is determined by whether or not there is a margin of proof strength, and there is a margin of proof strength that can handle the force of the follower, but this is also determined in consideration of the special characteristics of the entire building .
In this embodiment, all the main pillars A1, A3, A5, A7, A11, A16, and A18 described above are reinforced main pillars.
The main column A requiring reinforcement is represented by a double square surrounded by a slightly larger square in FIG.

Next, the beam B requiring reinforcement for directly or indirectly transmitting the force received by the follower column to the main columns A1, A3, A5, A7, A11, A16, A18 is specified. The reinforcement beam B that is required is also determined in consideration of the balance of the entire building.
In FIG. 2, the specified reinforcing beam B is indicated by a double line. That is, among the beams B1 to B27 provided between the columns A, the beams B1, B2, B10, B13, B9, B19, B25, and B26 are reinforcing beams that are required.

Then, the main column A requiring reinforcement and the beam B requiring reinforcement are reinforced. These reinforcing methods will be described later, but the point that the main pillar A and the main pillar B are reinforced, and the secondary pillar and the main pillar cooperate to receive the seismic force. explain.
For example, the follower pillar A2 at the wall is a follower pillar that is not reinforced, but the force received by the follower pillar A2 is transmitted to the reinforced main pillars A1 and A3 that are reinforced through the intersecting reinforcement beams B1 and B2. Can take charge.

In addition, the force is transmitted from the follower column A6 to the other reinforcement main column A7 through the reinforcement beam B10 so that the follower column A6 and the reinforcement main column A7 cooperate to exert the proof stress. Yes.
Similarly, the reinforcing main column A11 requires reinforcement from the follower column A12 via the reinforcing beam B19, the reinforcing main column A16 requires reinforcement from the subsidiary column A17 via the reinforcement beam B26, and the reinforcing main column A18 requires reinforcement. A force is transmitted from the follower column A15 via the beam B25.
Further, the force is transmitted from the follower column A10 via the reinforcement beam B9 to the reinforcement main column A5 which is located in the upper right corner of FIG. 2, and from the follower column A9 via the reinforcement beams B13 and B9. Force is also transmitted. These reinforced beams B13 and B9 are reinforced beams for indirectly transmitting the force received by the follower column A9 to the reinforced main column A5.

According to this reinforcing method, as described above, the force received by the follower column is transmitted directly or indirectly to the main column requiring reinforcement via the beam requiring reinforcement. Therefore, the force actually received by the follower post A is reduced, and the follower post A is not easily broken even if it is not reinforced. Even if the follower pillar A is subjected to such a force that it breaks, if the reinforced reinforcement beam B that crosses the follower pillar A is maintained, the entire building can be prevented from collapsing.
For example, even if a force that destroys the follower column A2 is applied, if the reinforcing beams B1 and B2 are maintained, the follower column A2 is lifted by the reinforcing beams B1 and B2, and the follower column There is no such thing as the building collapses at A2.
As described above, the strength of the building can be maintained without having to reinforce the follower pillar by giving the force required to the follower pillar to the main pillar requiring reinforcement.
Thus, the fact that there is a column that does not need to be reinforced means that the number of columns to be reinforced can be reduced.

The reinforcing structure of the reinforcing main pillar A and the reinforcing beam B may be any structure as long as the required strength can be achieved.
In FIGS. 3 to 5, as an example of reinforcement of the main column A requiring reinforcement along the wall 7 and the beam B requiring reinforcement, the main beam A2 requiring reinforcement between the main column A3 requiring reinforcement and the follower column A2 adjacent thereto is shown. A reinforcing structure is shown.
As shown in FIG. 3, on both sides of the wall 7, column-shaped reinforcing frame bodies 8 having a U-shaped cross section are vertically stacked on the lower part of the beam of the main column A 3 requiring reinforcement. The reinforcing frame body 9 for the crossing portion corresponding to the width of the beam B is laminated on the upper portion.
In this embodiment, since both sides of the wall 7 are the same structure, a one-side reinforcing structure will be described here.

The reinforcing frame body 8 for the column portion is arranged at a predetermined interval from the side surface of the main column A3 requiring reinforcement, and the end portion is abutted against the surface of the wall 7.
Further, the reinforcing frame body 9 for the intersecting portion includes an attachment piece 9 a that opens outward from one end portion, and the attachment piece 9 a is fixed to the beam B <b> 3 by a bolt 10. Further, the other end portion of the reinforcing frame body 9 is kept spaced from the opposing reinforcing beam B2 so that the end portion of the reinforcing frame body 11 for beams, which will be described later, is in contact therewith. .
And the axial streak 3 is arrange | positioned between the said reinforcement frame bodies 8 and 9 and the main pillar A3 required, and it fills with the filler 4 which is abbreviate | omitted in FIG. 3, and comprises the reinforcement layer. (See FIG. 4).

On the other hand, a reinforcing frame 11 for the beam is arranged on the side surface of the reinforcing beam B2 so as to be spaced from the side surface, and a pair of bending reinforcing bars 12 along the axis of the reinforcing beam B2 are provided on the inner side. It is arranged. Both ends of each bending reinforcement 12 are inserted into holding holes formed in the side surfaces of the adjacent columns A2 and A3.
The beam reinforcing frame 11 is a member having an L-shaped cross section as shown in FIG. 5, one end in the longitudinal direction is brought into contact with the side surface of the follower pillar A2, and the other end is used as the reinforcing frame for the crossing portion. It is made to contact the other edge part of the body 9 (refer FIG. 4). The beam reinforcing frame 11 is also filled with the filler 4 to form a beam reinforcement layer.

The beam reinforcing frame 11 can also be fixed to the bottom of the reinforcing beam B2 or the ceiling slab 13 indicated by a two-dot chain line.
Further, the reinforcing beam B1 opposite to the reinforcing beam B2 on the side of the follower column A2 is also reinforced in the same manner as the reinforcing beam B2.
Further, the other main pillars A requiring reinforcement A arranged along the wall 7 are also reinforced in the same manner as the main pillars a3 requiring reinforcement shown in FIGS.

However, the reinforcing main column A that requires no walls 7 and the reinforcing beam B that crosses the main column 7 can have a reinforcing structure different from that of the main column A3 that is required. Will be described.
Unlike the other main columns A requiring reinforcement, the main column A 7 requiring reinforcement is not continuous with the wall 7 (see FIG. 2). Therefore, as in the conventional example shown in FIG. A reinforcing layer is formed by surrounding the reinforcing frame 2. Since this reinforcing structure is the same as the conventional structure, a detailed description is omitted. However, the axial streak 3 is arranged in the space surrounded by the reinforcing frame 2, and the reinforcing layer of the column is formed by filling the filler 4. It is composed.
Then, as shown in FIG. 6, at the intersection where the beam B is connected in all directions, the reinforcing frame 9 for the intersection shown in FIG. 4 is divided into divided frames 9b and 9c with the beam B as a boundary. Are provided so as to sandwich the beams B6 and B15.

Further, since there is no wall 7 under the beam requiring reinforcement B10, a beam-shaped reinforcement frame 14 having a U-shaped cross section that is continuous at the bottom of the beam requiring reinforcement B can be used. However, the reinforcing structure of the reinforcing beam B10 may be the same as that shown in FIGS.
A bending reinforcing bar 12 along the axis of the beam B is disposed between the beam reinforcing frame 14 and the beam requiring reinforcement B10, and the filler 4 is filled therein. This filler 4 is integrated with the reinforcing layer of the main column A7 requiring reinforcement.

The reinforcing frame 14 may be brought into contact with the bottom of the reinforcing beam B10, or the beam may be kept between the bottom of the reinforcing beam B10 and the reinforcing frame 14 as shown in FIG. The filler 4 may be filled below.
The reinforcing frame 14 may also be fixed to the reinforcing beam B10 or the ceiling slab 13.
The main column A7 requiring reinforcement as described above can be responsible for the force received by the sub column A6 that is not reinforced via the beam B10 that requires reinforcement.

As mentioned above, although the reinforcement structure of the main pillar required reinforcement and the reinforcement required beam was demonstrated using FIGS. 3-7, these are examples and each reinforcement structure is not restricted to this.
For example, the reinforcing layer of the main column requiring reinforcement may be formed by fixing a concrete reinforcing layer formed in advance to the existing column instead of being configured by being surrounded by a reinforcing frame and filled with a filler.
Moreover, a tensile strength can also be added to a reinforcement frame body by adhere | attaching a strip | belt-shaped sheet | seat on the surface of the said reinforcement frame body for pillars, intersections, and beams.

Further, the reinforcement of the beam requiring reinforcement is not limited to the above-described reinforcement in which the bending reinforcing bar 12 is embedded in the filler 4. The number of the bending reinforcement bars 12 can be changed, or the bending reinforcement bars can be omitted.
In some cases, it is sufficient to reinforce the beam requiring reinforcement by simply attaching a belt-like sheet or a steel plate to the surface of the beam requiring reinforcement. If the existing bending reinforcement has sufficient strength, if the concrete on the beam surface can be prevented from sticking by adhering the belt-like sheet or steel plate, the existing bending reinforcement will function effectively. This is because power to the main pillar can be transmitted.

In any case, as described above, the number of columns to be reinforced can be reduced if the force can be reliably transmitted from the follower column to the main column via the reinforced reinforcing beam. As a result, the effect of reinforcing the building can be increased while suppressing the cost of the reinforcement work.
Moreover, although the reinforced pillar becomes thick by a reinforcement layer, if the number of such pillars can be reduced, it can also prevent that a living space becomes narrow.
In this embodiment, all the main pillars are reinforced. However, if there is a margin in proof stress without reinforcement, the force received by the sub pillars may be transmitted to the main pillars that are not reinforced. .

Moreover, you may identify the reinforcement required pillar which should be reinforced among the followers, and may reinforce it. If the follower column is reinforced, the force applied to the main column can be reduced accordingly.
Since the reinforcement required pillar is a pillar that transmits the force received by itself to the main pillar even if it is reinforced, the reinforcement of the reinforcement required pillar can be simplified compared to the reinforcement of the reinforcement required main pillar. For this reason, the reinforcement of the reinforcement required pillar can reduce the influence on the cost and the living space.

  It is particularly suitable for reinforcing buildings with many pillars.

A1 to A18 Columns B1 to B27 Beams A1, A3, A5, A7, A11, A16, A18 Main columns, main columns A2, A4, A6, A8, A9, A10 Secondary columns A12, A13, A14, A15, A17 Follower B1, B2, B10, B13, B9, B25, B26 Reinforced beam

Claims (2)

A method of reinforcing an existing building with a plurality of existing pillars,
Based on the particularity of the existing building, the plurality of existing pillars are divided into main pillars that handle forces acting on other pillars in cooperation with other pillars, and secondary pillars composed of the other pillars. A process of classification;
Identifying a pillar to be reinforced among the main pillars as a main pillar requiring reinforcement;
Identifying a beam for transmitting the force received by the follower column directly or indirectly to the main column requiring reinforcement as a beam requiring reinforcement;
A method for reinforcing an existing building, comprising: a step of reinforcing the reinforcing main column and the reinforcing beam. A step of identifying a pillar to be reinforced among the followers as a reinforcement follower required;
The reinforcement method of the existing building of Claim 1 provided with the process of reinforcing the said reinforcement required pillar.

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