JP2010196285A - Method for reinforcing existing structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for reinforcing an existing structure, which facilitates construction, and which can increase the shear strength, rigidity and bending strength of the reinforcing target section of the existing structure. <P>SOLUTION: In this method for reinforcing the existing structure, the reinforcing target section is reinforced by integrating the reinforcing target section of the existing structure 2 with a reinforcing plate. A fiber concrete plate 3 with a compressive strength of 150 N/mm<SP>2</SP>or more, a bending strength of 20 N/mm<SP>2</SP>or more, and a tensile strength of 8 N/mm<SP>2</SP>or more is used as the reinforcing plate 2. An integration means for integrating the reinforcing target section of the existing structure and the reinforcing plate together includes a mechanical joint element for attaching the fiber concrete plate to the reinforcing target section, and a grout material 16 for being infilled into a grout filling space 15 formed between the reinforcing target section and the fiber concrete plate attached to the reinforcing target section by the mechanical joint element. An extension section extended by the integration means and the fiber concrete plate is anchored to an existing section (column 40), except the reinforcing target section of the existing structure adjacent to the extension section. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for reinforcing an existing structure that is easy to construct and can increase the shear strength, rigidity, and bending strength of a portion to be reinforced of the existing structure.

  There is known a seismic reinforcement method for an existing structure in which a reinforcing material such as a steel plate is attached to a column or beam of an existing reinforced concrete structure to reinforce the column or beam.

Japanese Patent Laid-Open No. 10-152997

As a method of seismic reinforcement for existing structures, there is a method to increase the strength of the whole structure by increasing the thickness of pillars, beams, walls, etc. In this case, the extension part and the existing part must be integrated. I must. Moreover, it is necessary to arrange | position a tension reinforcement and a shear reinforcement in an expansion part as needed. In other words, it is necessary to perform an integration work of the additional part and the existing part and a reinforcing bar arrangement work. In the reinforcing method of Patent Document 1, in order to integrate the additional part and the existing part, the number of anchor bolts for attaching the reinforcing material to the pillar or beam has to be increased, and the reinforcing bar arrangement work is also required. There was a problem that the construction was difficult.
The present invention simplifies the integration work of the extension part and the existing part, eliminates the need for reinforcing bar arrangement work, is easy to construct, and provides the shear strength, rigidity, bending strength of the reinforcement target part of the existing structure. Provided is a method for reinforcing an existing structure that can increase the

The reinforcement method for an existing structure according to the present invention is a reinforcement method for an existing structure in which the reinforcement target portion and the reinforcement plate of the existing structure are integrated to reinforce the reinforcement target portion. / mm ² or more, a bending strength of 20 N / mm ² or more, tensile strength using 8N / mm ² or more fiber concrete board, integrated means to integrate the reinforcing target portion of the existing structure and the reinforcing plate, fiber A mechanical joint element for attaching a concrete plate to a reinforcement target portion, and a grout material filled in a grout filling space formed between the fiber concrete plate attached to the reinforcement target portion by the mechanical joint element and the reinforcement target portion The extension part that is constructed by the integration means and the fiber concrete board is fixed to the existing part other than the reinforcement target part of the existing structure adjacent to the extension part. In this way, the thickness of reinforcing parts such as pillars, beams, walls, floors, etc. of existing structures is increased using high-strength fiber concrete boards, so lightweight and compact high-strength fiber concrete boards should be used. Therefore, it is possible to simplify the integration work between the additional part and the existing part, eliminate the need for the reinforcing bar placement work, simplify the construction, and increase the shear strength and rigidity of the reinforcement target part of the existing structure. In addition, since the extension portion is fixed to an existing portion other than the reinforcement target portion of the existing structure adjacent to the extension portion, the bending strength of the reinforcement target portion can be increased.
In addition, by installing reinforcing reinforcing bars across the grout part formed in the extension part and the inside of the existing part, the extension part is fixed to the existing part, or the extension part and the surface of the existing part are straddled. By affixing the fiber reinforcement sheet, the bending strength of the portion to be reinforced can be increased by fixing the additional portion to the existing site.

The figure which shows the earthquake-proof reinforcement structure with which the beam was reinforced (form 1). The longitudinal cross-sectional view (form 1) of an earthquake-proof reinforcement structure. The longitudinal cross-sectional view which shows the mechanical joining element vicinity of an earthquake-proof reinforcement structure (form 1). A cross-sectional view of a seismic reinforcement structure (form 1). Cross-sectional view (form 1) which shows fixation with an earthquake-proof reinforcement structure and a pillar. Cross section (form 2) which shows fixation with an earthquake-proof reinforcement structure and a pillar. The longitudinal cross-sectional view (other example) of an earthquake-proof reinforcement structure using a beam penetration bolt. The cross-sectional view which shows that the end surface of the fiber concrete board was made into the plane (other example). The longitudinal cross-sectional view (other example) of an earthquake-proof reinforcement structure using the bolt which protrudes from the surface of a beam.

Form 1
As shown in FIG. 1, the seismic reinforcement structure 1 according to the first aspect includes an existing structure 2 such as a reinforced concrete structure, and reinforcement target parts such as columns, walls, beams, and floors of the existing structure 2. The fiber concrete plate 3 as a reinforcing plate attached to the fiber, the integration means 4 for integrating the fiber concrete plate 3 and the portion to be reinforced, and the expansion constituted by the integration means 4 and the fiber concrete plate 3 Fixing means 6 for fixing the portion 5 to an existing portion of the existing structure 2 other than the reinforcement target portion adjacent to the additional portion 5 is provided. In addition, in FIG. 1, the example which reinforced the beam 10 as a reinforcement object part of the existing structure 2 with the fiber concrete board 3 is shown.

The fiber concrete board 3 is a concrete board formed by mixing fibers such as steel fibers and organic fibers. For example, the compressive strength is 150 N / mm ^{2 to} 200 N / mm ² , and the bending strength is 20 N / mm ² to. 50 N / mm ^2, a tensile strength of ultra high strength fiber reinforced concrete thin plate of ^{8N / mm 2 ~12N / mm 2} . The fiber concrete board 3 is manufactured at a factory. For example, the fiber concrete board 3 has a rectangular size of a long side length of 1000 mm, a short side length of 800 mm, and a thickness of 10 mm. Easy. Therefore, the work which handles the fiber concrete board 3 becomes easy on the spot.

  The fiber concrete board 3 is equipped with the bolt through-hole 9 which penetrates the surface 3a and the back surface 3b of the fiber concrete board 3 (refer FIG. 2). The bolt through holes 9 are provided at intervals of, for example, 500 mm. Furthermore, the fiber concrete board 3 includes a grout injection hole 11 and an air escape hole 12 that penetrate through the front surface 3 a and the back surface 3 b of the fiber concrete board 3.

The integration means 4 is composed of a mechanical joining element 13 and a grout material 16.
The mechanical joining element 13 is a bolt and a nut for attaching the fiber concrete board 3 to a reinforcement object part. The grout material 16 is filled in a grout filling space 15 formed between the fiber concrete plate 3 attached to the reinforcement target portion by the mechanical joining element 13 and the reinforcement target portion.

The reinforcement method of the reinforcement object part is demonstrated. Here, a method of reinforcing the beam 10 as the reinforcement target portion of the existing structure 2 will be described as an example. First, the surface 10a of the beam 10 of the existing structure 2 is roughened. That is, the surface 10a of the beam 10 of the existing structure 2 is formed into an uneven surface. Next, the fiber concrete plate 3 is attached to the beam 10 using bolts 18 and nuts 19 so that the back surface 3b of the fiber concrete plate 3 and the surface 10a of the beam 10 face each other with a predetermined interval (for example, about 10 mm). By attaching, the grout filling space 15 is formed between the back surface 3b of the fiber concrete board 3 and the surface 10a of the beam 10. The grout filling space 15 is filled with a grout material 16 such as mortar or epoxy adhesive. Therefore, the fiber concrete board 3 and the beam 10 are integrated by the adhesive force by the grout material 16 and the mechanical joining element 13. Since the beam width of the beam 10 is increased by the additional portion 5 increased by the fiber concrete plate 3 and the integration means 4, the shear strength of the beam 10 and the rigidity of the beam 10 are increased. Moreover, since the fiber concrete board 3 is high intensity | strength, intensity | strength and rigidity increase by reinforcement with a thin board.
Further, the fixing means 6 is used to fix the extension portion 5 adjacent to the pillar 40 which is an existing part other than the reinforcement target portion to the pillar 40.

  Specifically, as shown in FIGS. 2 and 3, the integration means 4 includes a nut 19 provided inside the beam 10 so that a bolt 18 can be screwed from the surface 10a of the beam 10, and the nut. A bolt 18 such as a hole-in anchor screwed to 19, the bolt through hole 9 provided in the fiber concrete plate 3, and an end of the bolt through hole 9 close to the surface 3 a of the fiber concrete plate 3. The bolt head accommodation hole 20 and the grout material 16 filled in the grout filling space 15 are constituted. Accordingly, with the back surface 3b of the fiber concrete plate 3 and the surface 10a of the beam 10 facing each other so that the position of the bolt through hole 9 and the position of the nut 19 are aligned, the bolt 18 is passed through the bolt through hole 9 and the nut. Fasten to 19. At this time, the fiber concrete board 3 is placed so that the grout filling space 15 is formed between the back surface 3b of the fiber concrete board 3 and the surface 10a of the beam 10 with the bolt head 21 housed in the bolt head housing hole 20. Install. That is, as shown in FIG. 2, the fiber concrete board 3 is installed so that both the side surfaces 25; 25 of the beam 10 and the bottom face 26 of the beam 10 may be covered. In addition, if the fiber concrete board 3 which covers the bottom face 26 is provided, bending strength and shear strength will increase, but the fiber concrete board 3 which covers the bottom face 26 does not need to be provided. In this case, the grout filling space 15 may be formed by closing the lower end opening of the space formed by the side surfaces 25; 25 of the beam 10 and the back surface 3b of the fiber concrete plate 3 with a plate or the like.

  In addition, as shown in FIG. 4, when attaching the some fiber concrete board 3 to the beam 10, the end surfaces of the fiber concrete board 3 which mutually adjoins are faced | matched, and the edge part of each fiber concrete board 3 faced | matched is shown. By sticking the fiber reinforced sheet 30 to the surface using an adhesive, the fiber reinforced sheet 30 connects the fiber concrete plates 3 adjacent to each other. Thus, the grout filling space 15 is formed between the back surface 3b of the fiber concrete plate 3 and the surface 10a of the beam 10 by attaching the fiber concrete plate 3 to the surface 10a side of the beam 10. Then, the grout filling space 15 is filled with the grout material 16 from the grout injection hole 11 of the fiber concrete plate 3 at the position corresponding to the lower side of the beam 10. In this case, if the grout filling space 15 is filled with the grout filling hole 15 from the grout filling hole 11, air is discharged from the air escape hole 12 positioned above the grout filling hole 11, so that the grout filling 16 is filled with the grout filling 16. The space 15 can be filled smoothly. As the grout material 16 filled in the grout filling space 15 is solidified, the plurality of fiber concrete plates 3 and the beams 10 are integrated. Since the beam width of the beam 10 is increased by the additional portion 5 constituted by the integration means 4 and the fiber concrete plate 3, the shear strength and rigidity of the beam 10 are increased. Moreover, since the fiber concrete boards 3 adjacent to each other are connected by the fiber reinforcing sheet 30, the integrity of the fiber concrete boards 3 can be ensured. Therefore, even in the construction in which a plurality of fiber concrete plates 3 are connected to each other, a reinforcing effect equivalent to that of continuous large plates can be obtained.

  As shown in FIG. 4, the end surfaces of the pair of fiber concrete plates 3 that are brought into contact with each other are formed on the uneven end surfaces 33 and 33 that engage with each other. Thereby, the shift | offset | difference to the thickness direction of the edge parts of the fiber concrete board 3 can be prevented.

  Since the fiber concrete board 3 is provided with the bolt head accommodation hole 20 for accommodating the bolt head 21, as shown in FIG. 3, a decorative sheet is used by using an adhesive on the surface 3 a of the fiber concrete board 3 connected to the beam 10. When 28 is affixed, the surface of the decorative sheet 28 is prevented from protruding by the bolt head 21.

  For example, as shown in FIG. 5, the fixing unit 6 is formed by a reinforcing bar 42 having one end 41 embedded in the pillar 40 and the other end embedded in a grout that is a part of the additional portion 5. As this reinforcing steel bar 42, for example, a reinforcing bar having a structure of an embedded portion 35 (chemical type or driving type) such as an anchor bolt for post-installation is used. The embedded portion 35 is embedded in the pillar 40 adjacent to the additional portion 5, and the reinforcing reinforcing bar portion protruding from the pillar 40 is embedded in the grout material 16 of the additional portion 5 adjacent to the pillar 40. That is, the fixing means 6 formed by the reinforcing reinforcing bars 42 replaces the extension portion 5 added by the integration means 4 and the fiber concrete board 3 with a portion other than the reinforcement target portion of the existing structure 2 adjacent to the extension portion 5. Fix to existing site. In other words, by installing the reinforcing reinforcing bars 42 so as to straddle the grout part formed in the extension part 5 adjacent to the pillar 40 and the inside of the pillar 40, the extension part 5 other than the beam 10 that is the reinforcement target part. It fixed to the pillar 40 which is an existing site | part. The fiber concrete plate 3 attached so as to be adjacent to the column 40 includes a column surface 46 parallel to the side surfaces 25; 25 of the beam 10 and the surface 3a of the fiber concrete plate 3 that is already installed and closest to the column 40 side. It is installed diagonally so as to connect.

According to the first, for example, compressive strength ^{150N / mm 2 ~200N / mm 2} , bending strength ^{20N / mm 2 ~50N / mm 2} , a tensile strength of high strength of ^8N / mm ^{2 ~12N} / mm 2 Since the thickness of the beam 10 of the existing structure 2 is increased by using the fiber concrete board 3, the lightweight and small high-strength fiber concrete board 3 can be used. 5 and the beam 10 can be integrated easily by hand, and the rebar placement operation in the grout filling space 15 is not required, so that the construction is facilitated. The external force is resisted by the total area of the cross-sectional area of the additional portion 5 and the cross-sectional area of the beam 10 that is the existing portion, so that the shear strength and rigidity of the beam 10 that is the reinforcement target portion of the existing structure 2 are resisted. Can be raised.
Further, by installing a reinforcing bar 42 as the fixing means 6 across the grout portion formed in the extension portion 5 of the beam 10 and the inside of the pillar 40 adjacent to the extension portion 5 of the beam 10, the beam 10 Since the additional portion 5 is fixed to the column 40, the reinforcing bar 42 transmits the tensile force transmitted to the beam 10 to the column 40, so that the bending strength of the beam 10 can be increased.
In addition, since the strength of the fiber concrete plate 3 is higher than that of the conventional method in which a PC (precast concrete) plate is attached to the reinforcement target portion, the installation interval of the bolts 18 can be reduced to about 500 mm, and the number of bolt mounting locations can be reduced. Can be easy.
Moreover, since the fiber concrete board 3 itself functions as a mold for filling the grout filling space 15 with the grout material 16, a dedicated mold is not required and the cost can be reduced.

Form 2
The extension part 5 was fixed to the existing part by sticking the fiber reinforcing sheet 30 as the fixing means 6 across the surface of the extension part 5 and the surface of the existing part with an adhesive. For example, as shown in FIG. 6, by attaching a fiber reinforced sheet 30 across the surface 51 of the additional portion 5 of the beam 10 adjacent to the column 40 and the column surface 46 of the column 40, the additional portion 5 is changed to the column. Since the fiber reinforcing sheet 30 transmits the tensile force transmitted to the beam 10 to the column 40, the bending strength of the beam 10 can be increased.

As the bolt of the integration means 4, as shown in FIG. 7, a through bolt 45 that penetrates the beam 10 as a reinforcement target portion may be used. 5 and 6, the structure using the through bolt 45 as the bolt of the integration means 4 is illustrated, but it is needless to say that the bolt 18 shown in FIG. 3 may be used as the bolt of the integration means 4. is there.
As shown in FIG. 8, it is good also as a form which makes the end surface of a pair of fiber concrete board 3 mutually abutted into a plane, and flat end surfaces just face each other.
As shown in FIG. 9, a bolt 18a such as a post-installed anchor bolt that is embedded in the beam 10 and protrudes from the surface of the beam 10 is protruded from the surface 3a of the fiber concrete plate 3, and a nut 20a is provided on the bolt 18a. You may make it conclude.
As the fiber reinforcing sheet 30, an FRP fiber sheet containing carbon or aramid may be used.
The fiber concrete board 3 may have a configuration in which reinforcing reinforcing bars 42 are arranged inside.
The fiber concrete board 3 may have a shape such as a box shape, a U shape, or an L shape.
The fiber concrete board 3 may have a compressive strength of 150 N / mm ² or more, a bending strength of 20 N / mm ² or more, and a tensile strength of 8 N / mm ² or more.

  The reinforcing method of the present invention can be similarly applied to the case of reinforcing a wall, a column, or a floor as a reinforcement target portion.

2 Existing structures, 3 fiber concrete boards, 4 integration means, 5 additional parts,
6 fixing means, 13 mechanical joining elements, 15 grout filling space,
16 grout material, 30 fiber reinforced sheet.

Claims (3)

In the reinforcing method of an existing structure in which the reinforcement target portion and the reinforcement plate of the existing structure are integrated to reinforce the reinforcement target portion, the compression strength is 150 N / mm ² or more and the bending strength is 20 N / mm ² as the reinforcement plate. As mentioned above, the mechanical means for attaching the fiber concrete board to the reinforcement object part using the fiber concrete board having a tensile strength of 8 N / mm ² or more and integrating the reinforcement object part and the reinforcement board of the existing structure. An integrated means and a fiber concrete board comprising an element, a fiber concrete plate attached to a reinforcement target portion by a mechanical joining element, and a grout material filled in a grout filling space formed between the reinforcement target portion The method for reinforcing an existing structure is characterized in that the additional part added by the above is fixed to an existing part other than the target part of the existing structure adjacent to the additional part.   2. The reinforcement of an existing structure according to claim 1, wherein the reinforcing part is fixed to the existing part by installing a reinforcing bar across the grout part formed in the extension part and the inside of the existing part. Method.   The method for reinforcing an existing structure according to claim 1, wherein the additional portion is fixed to the existing portion by sticking a fiber reinforcing sheet across the surface of the additional portion and the surface of the existing portion.

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