JP3521372B2 - Building frame reinforcement structure - Google Patents

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 a building frame, and more particularly to a reinforcing structure for seismically reinforcing an existing building frame.

[0002]

2. Description of the Related Art As a method of increasing the proof stress of an existing building,
There is a method of adding a reinforced concrete wall in the opening surrounded by columns and beams, or a method of incorporating and joining a steel frame with braces in the opening.

FIG. 3 shows an example in which a reinforced concrete wall body is additionally installed in an opening surrounded by columns and beams to reinforce the frame. Here, how to add the additional wall body 3 to the upper beam 1 forming the opening 2 is shown. In this case, first, as shown in FIG. 1A, the post-installed anchor 5 with a head is driven into the concrete 1b of the beam 1 from the surface 1a on the opening 2 side while avoiding the beam rebar 1c. Then, as shown in FIGS. (B) and (c), the reinforcing bar 7 that constitutes the wall body 3 is incorporated into the opening 2, the spiral hoop 4 is arranged at the upper end, and the dowel reinforcing bar 6 on the wall side 3 is attached. It is connected to the post-installed anchor 5 through the gap of the spiral hoop 4. In this state, by pouring concrete 8, the wall body 3 incorporated in the opening 2 is joined to the beam 1 or the column to reinforce the frame composed of the column and the beam.

FIG. 4 shows another conventional example. In this example, a steel frame 16 having braces 15 attached (also referred to as a wall body in the present specification) is incorporated into the opening 2 surrounded by the pillar 11 and the beam 1 to join the pillar 11 and the pillar 11.
The frame consisting of and beam 1 is reinforced. Also in this case, the post-installed anchor bolt 18 is driven into the surface of the column 11 and the beam 1 on the side of the opening 2. Further, a headed stud 17 is provided on the outer periphery of the steel frame 16, a spiral hoop 19 is arranged in a gap between the steel frame 16 and the peripheral portion of the opening 2, and cast-in-place concrete (including mortar) 20 is placed in the gap. By doing so, the steel frame 16 and the existing frame (column 11, beam 1) are joined.

By the way, in the above-mentioned conventional example, a large number of post-installed anchors 5 and 18 embedded in the existing skeleton (upper beam 1 in FIG. 3, pillar 11 and upper beam 1 in FIG. 4) are used to reinforce the existing skeleton. Although the wall body 3 as a member or the steel frame 16 with the brace 15 is integrated, the post-installed anchors 5 and 18 cannot be installed when a resident is present because of the violent noise and dust. Further, due to the reinforcing bars and steel frames in the existing body, the places where the post-installed anchors 5 and 18 are driven are limited, and there is a problem that the workability is poor.

Therefore, as a structure in which the driving of the post-installed anchors 5 and 18 is reduced as much as possible, as shown in FIG.
As shown in (b), a large number of convex cotters 10 are adhered to a surface 1a on the opening 2 side of a beam 1 which is an existing skeleton at intervals along a peripheral edge of the opening 2, and these cotters 10 are wall-mounted. It is considered that the reinforcing wall body 3 is integrated with the existing frame (beam 1) by placing the concrete 8 of the wall body 3 so as to be included in the thickness center.

In this case, since the in-plane shearing force in the direction along the surface of the opening 2 can be sufficiently transmitted between the existing frame (beam 1) and the reinforcing wall body 3 via the cotter 10, Post-installed anchors and dowels for transmitting in-plane shear force can be omitted. However, since the out-of-plane shearing force in the direction intersecting the plane of the opening 2 cannot be sufficiently transmitted by the cotter 10 alone, the post-installed anchor 5 is driven between the cotters 10 and the wall member is inserted therein. The dowel rebar 6 on the 3 side is fitted and then the concrete 8 is cast to transmit the out-of-plane shearing force.
Reference numeral 9 is a knit muscle.

[0008]

By the way, in the above-described conventional reinforcing structure using the cotter 10, as shown schematically in FIG. 6, the cotters 10 are separated one by one (divided into pieces) and the existing skeleton ( Since it is bonded to the beam 1) here, the part that effectively contributes to the transmission of force is the beam 1 that bonds the cotter 10.
The surface area was about 1/2. That is, since the bonded portion is limited to the range indicated by the symbol A, the shear force transmission efficiency was low. Also, since each cotter is independent, if the adhesive surface of each cotter itself breaks, the cotter will slip and lose its force transmission function, and the proof strength of the entire reinforcing wall body may drop sharply. was there. In addition, since it is necessary to individually bond a large number of cotters, there is a problem in that the number of cotters requires a lot of bonding work.

In view of the above circumstances, it is an object of the present invention to provide a reinforcing structure for a frame of a building which can improve the reinforcing performance and facilitate construction.

[0010]

According to a first aspect of the present invention, in a structure in which a frame of a building is reinforced by adding a wall body in an opening surrounded by columns and beams of an existing building, the structure of the columns and beams is improved. On the opening side surface, a joining member made of precast concrete, in which a plurality of convex cotters are continuously provided and integrated on one substrate, is provided.
It is characterized in that the concrete of the wall body is cast on site so that the joint members are adhered side by side without a gap and the joint member is included in the middle portion in the thickness direction.

Further, the invention of claim 2 is characterized in that the reinforcing bars are continuously arranged in the plurality of convex cotters of the joining member.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows a reinforcing structure according to an embodiment of the present invention. This reinforced structure is similar to the conventional reinforced structure shown in FIG. 5, in which a wall made of reinforced concrete is incorporated into the opening surrounded by columns and beams, and the outer peripheral portion is joined to the existing skeleton to create an existing skeleton. It is a reinforced skeleton.

This reinforcing structure is an improvement of the conventional reinforcing structure shown in FIG. 5. As shown in FIG. 1 (a), an opening surface is formed on a surface 1a on the opening 2 side of an existing frame such as a pillar or a beam 1. The joining member 30 is adhered as a member for transmitting the in-plane shearing force in the direction along (the surface of the opening 2), and the concrete 8 of the wall body 3 is cast so that the joining member 30 is included in the center of the wall thickness. is doing.
The joining member 30 is made of precast concrete having a structure in which a plurality of convex cotters 32 each having a trapezoidal shape in a front view are continuously arranged on a substrate 31 having a predetermined thickness at regular intervals. These joining members 30 are fixed to the beam 1 by arranging and adhering the substrates 31 to the surface 1a of the beam 1 on the side of the opening 2 side by side without a gap, whereby the cotters 32 as convex portions are arranged at a constant pitch. I'm out. In this case, continuous reinforcing bars 33 are embedded through the substrate 31 in the plurality of convex cotters 32 of each joining member 30 to enhance the strength of the cotter 32. Other configurations are the same as those in FIG.

In this reinforcing structure, since the joining member 30 in which a plurality of cotters 32 are arranged in series is adhered to the existing frame (here, the beam 1), the bonding surface can be wide and the existing frame can be bonded. Effective use of the entire surface area, cotter 32
And the joint strength of the existing body can be increased. Therefore,
As a result, the ability to transmit the shearing force between the joint member 30 integrally including the cotter 31 and the wall body 3 is enhanced. Further, since the plurality of cotters are connected via the substrate 31, even if the adhesive surface corresponding to a part of the cotters 31 is broken, the joining member 30 is used.
The cotter 31 does not slide until the entire bonding surface of the cotter is broken. Therefore, as shown in FIG. 2, it is possible to suppress a rapid decrease in yield strength as in the conventional case. Moreover, since the joining member 30 in which the plurality of cotters 32 are provided in series is adhered to the existing frame, the number of adhering steps is reduced and the construction is simplified.

In the above embodiment, the case where the wall body 3 made of reinforced concrete is incorporated in the opening 2 to reinforce the skeleton is shown. However, as shown in FIG. 4, the steel frame 16 with the brace 15 is reinforced. The present invention can also be applied to the case of being incorporated in the opening 2 as a wall body. In that case, instead of the post-installed anchor, the joining member 30 in which the plurality of cotters 32 are continuously provided is bonded to the existing frame, and the joining member 30 is included in the center in the thickness direction so that the steel frame 16 and the existing frame are included. If concrete (including mortar) 20 is cast on site in the gap between the skeletons,
The same effect as that of the above embodiment is obtained.

[0016]

As described above, according to the first aspect of the present invention, the joining member in which a plurality of cotters are arranged in series is adhered to the existing skeleton side by side without a gap , instead of the conventional individual cotter. The bonding surface between the existing skeleton and the existing skeleton can be widened, and the entire bondable surface area of the existing skeleton can be effectively used to increase the bonding strength between the cotter and the existing skeleton. As a result, the ability to transmit the shearing force between the existing skeleton and the wall through the joining member is enhanced. Further, since the plurality of cotters are connected via the substrate, even if the adhesive surface corresponding to some of the cotters is broken, the cotter does not slip until the entire adhesive surface of the joining member is broken. Therefore, it is possible to suppress a rapid decrease in yield strength as in the conventional case, and it is possible to enhance the reinforcing performance of the frame by incorporating the wall body. Moreover, since the joining member in which a plurality of cotters are arranged in series is adhered to the existing body, the number of adhering steps can be reduced and the construction can be rationalized. Further, as in the invention of claim 2, by disposing continuous reinforcing bars in each cotter, the strength of the cotter can be increased and the reinforcing performance can be further enhanced.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, in which (a) shows a part of a structure in which a reinforcing wall body is integrally incorporated into an opening of a frame by using a joining member in which a plurality of cotters are continuously provided. The sectional view seen from the front is shown, and (b) is a sectional view showing the joining member in which the reinforcing bars are continuously embedded in the cotter portion.

FIG. 2 is a characteristic diagram showing a comparison of the yield strengths of the structure of the embodiment of the present invention and the structure using a conventional cotter.

FIG. 3 is a view showing an example of a conventional reinforcing structure, (a) is a cross-sectional view showing a state in which a post-installed anchor is driven into concrete of a beam, and (b) is incorporated into an opening using the anchor. FIG. 3C is a vertical cross-sectional view showing a state in which the reinforcing wall body is being joined to the beam, and FIG.

4A and 4B are views showing another example of a conventional reinforcing structure, FIG. 4A is a sectional view seen from the front, and FIG. 4B is a longitudinal sectional view vertically divided in a direction perpendicular to a wall body.

FIG. 5 is a view showing still another example of the conventional reinforcing structure,
(A) is a vertical cross-sectional view vertically divided into a wall body,
(B) is sectional drawing seen from the front of a wall.

FIG. 6 is a cross-sectional view seen from the front, showing a simplified main part of the structure of FIG.

[Explanation of symbols]

1 beam 1a Open side 2 openings 3 Reinforced concrete wall 8 concrete 30 joining members 31 substrate 32 convex cotter 33 Rebar 16 Steel frame with braces (wall) 20 concrete

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-4-146349 (JP, A) JP-A-53-126728 (JP, A) Fukuikai 3-95407 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) E04G 23/02 E04H 9/02 321

Claims (2)

(57) [Claims] 1. In a structure in which a frame of a building is reinforced by adding a wall body in an opening surrounded by columns and beams of an existing building, one substrate is provided on a surface of the columns and beams on the opening side. A plurality of convex cotters are continuously connected to and integrated with each other to join and join the precast concrete joining members side by side without a gap , and the concrete of the wall body is cast on site so that the joining members are included in the middle portion in the thickness direction. Reinforcement structure of building frame characterized by that. 2. The reinforcing structure for a building frame according to claim 1, wherein reinforcing bars are continuously arranged in a plurality of convex cotters of the joining member.