JP3633814B2 - Seismic retrofit method for existing structures - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a seismic retrofit method applied to, for example, retrofitting existing structures such as hospitals and office buildings.
[0002]
[Prior art]
Conventionally, when the seismic performance is lower than a predetermined reference value in the existing structure as described above, an opening is formed by removing the insufficient part of the wall of the existing structure or the existing low-strength wall, etc. A seismic retrofitting method is known in which an RC (steel reinforced concrete) bearing wall is added in the opening to increase the strength of the entire structure.
[0003]
FIGS. 5 to 7 show construction examples of the conventional seismic retrofit method. First, anchor bolts 1 of about 150 to 200 mm are attached to a frame R such as a column or beam on the inner surface of the opening S formed in the existing structure. Place at the pitch. On the other hand, in the portion where the bearing wall W is formed, the reinforcing bars 2 are arranged in a grid pattern at a predetermined pitch and in two rows (double), and are supported at positions where they are connected to the frame such as columns and beams. The spiral muscle 3 for preventing destruction is inserted. Then, form frames (not shown) are assembled on both sides of the reinforcing bar, concrete is cast in to form a bearing wall W, and the anchor bolt 1 is used as a connecting bar, such as a column or beam on the inner surface of the opening. And the newly formed bearing wall W are integrated.
[0004]
[Problems to be solved by the invention]
By the way, it is preferable that the anchor bolt 1 to be placed on the side of the driving body is further provided straight to the frame so as to be positioned at the center of the two rows of reinforcing bars on the bearing wall side. However, it is difficult to always drive a large number of anchor bolts straight to the housing. In addition, when drilling a concrete body for anchor bolting, it is necessary to shift the drilling position to avoid rebar cutting because a drill hits the reinforcing bar originally embedded in the drilling position. Bolts may not be driven as designed. In addition, many anchor bolts have to be hit from the role of joining bars, and since the pitch is narrow, it is difficult to shift the position, and construction takes time. When placing anchor bolts, noise, vibration, and dust are generated during drilling. If a large number of anchor bolts are to be placed, the use of buildings that should be earthquake-proofed must be temporarily suspended. . Therefore, it is an issue to perform earthquake-proof repair with high accuracy and as short a construction period as possible.
[0005]
The present invention has been proposed in view of the above-described problems, and an object thereof is to provide a seismic repair method capable of easily and quickly retrofitting existing structures.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, an earthquake-proof repair method for an existing structure according to the present invention has the following configuration.
[0007]
In other words, on the inner surface of the opening formed in the existing structure to be seismically reinforced, while arranging and fixing a substrate made of a channel type steel material in which a large number of stud gibels are implanted in the longitudinal direction, a reinforcing bar is arranged in the opening, Spiral reinforcement for preventing bearing failure is inserted at the position where the reinforcing bar is connected to the frame at the periphery of the opening, and concrete is placed in the opening so as to embed the spiral reinforcement, the reinforcing bar and the stud gibber. And building a bearing wall.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the earthquake-proof repair method of the existing structure by this invention is demonstrated concretely based on a figure. FIG. 1 is a front view showing a construction example of the seismic retrofit method according to the present invention, FIG. 2 is a partial enlarged view thereof, and FIGS. 3 (a) and 3 (b) are cross-sectional views taken along lines AA and BB in FIG. 4 and 4 are explanatory views showing an example of a construction process, and members having the same functions as those in the conventional example will be described with the same reference numerals.
[0009]
In carrying out the earthquake-resistant repair method of the present invention, the opening S is first formed in the outer wall of an existing structure such as a concrete building to be earthquake-proofed, and there is an existing wall or sash at that location. Is removed to form an opening of a predetermined size. In that case, it is desirable to remove all the walls in the region surrounded by the pillars and beams, so that the entire periphery of the opening is surrounded by the pillars and beams.
[0010]
In place of the anchor bolt 1 in the conventional example, a substrate 10 in which a large number of stud dowels 11 are implanted is installed and fixed on the inner surface of the opening S formed as described above. In the present embodiment, the substrate 10 is made of a channel-shaped steel material, and the above-described stat gibels 11 are implanted in one or two rows at a substantially central portion of the inner surface of the base portion. The stud dowel 11 is formed in a round bar shape having a large-diameter head portion 11a at one end by a metal steel material or the like, and has an end portion opposite to the head portion 11 fixed to the substrate 10 by welding or the like in advance. Further, as shown in FIG. 1, a large number of stud gibels 11 are provided at substantially equal intervals in the longitudinal direction of the substrate 10, and the pitch thereof is set to about 150 to 200 mm, similar to the anchor bolt 1 in the conventional example. .
[0011]
Each of the substrates 10 is attached to the housing R on the inner surface of the opening S with an adhesive 12 and a plurality of anchor bolts 13. In the case of the figure, the inner surface of the opening S, the substrate 10 and Each substrate 10 is attached by a so-called post-filling type epoxy resin adhesive 12 that is filled with an adhesive later, and four anchor bolts 13 arranged at substantially equal intervals with a pitch of about 900 mm. The anchor bolts 13 are all screw bolts in this example, and are fixed by being inserted together with an adhesive into holes formed in the inner surface of the opening S as shown in FIG. 3 (b). The substrate 10 is fixed by a nut 14 screwed into a bolt 13. In the present embodiment, the substrate 10 and the stud dowel 11 are provided on the four circumferences of the opening S as shown in FIG. 1. In FIG. Is omitted in the figure.
[0012]
Next, as shown in FIG. 4B, the reinforcing bars 2 are arranged on the inner side of the substrate 10 and the stud dowel 11 fixed to the inner surface of the opening S as described above. In the present embodiment, the reinforcing bars 2 are arranged in a lattice pattern as shown in FIGS. 1 and 2 at a predetermined pitch as in the prior art, and in two rows (double) as shown in FIG. Spiral muscles 3 for preventing bearing failure are inserted at the positions where the peripheral pillars and beams are connected. Its spiral muscle 3 is provided on the entire circumference circumferential direction unillustrated opening surface, in FIG. 2 shows only a portion.
[0013]
Next, a mold frame (not shown) is assembled on both sides of the substrate 10 so as to close the substantially entire surface of the opening S, and concrete is placed in the mold frame so that the bearing walls W are formed as shown in FIG. The pillars and beams on the periphery of the opening and the load-bearing wall W are integrated with the anchor bolt 1 as a joining bar.
[0014]
In the above embodiment, as a means for attaching the substrate 10, the anchor bolt 13 is inserted and fixed together with an adhesive into a hole formed in the inner surface of the opening S, and the substrate is fixed by the nut 14 screwed into the anchor bolt 13. 10 is fixed, for example, using an expandable anchor or the like.
[0015]
Further, the substrate 10 is fixed to the inner surface of the opening with the adhesive 12 and the anchor bolt. However, an expandable anchor or the like may be used in place of the anchor bolt, and such an anchor bolt or an expandable type may be used. it is also possible to mount only the adhesive without an anchor or the like and Mochiiruko.
[0016]
【The invention's effect】
As described above, the seismic retrofit method for an existing structure according to the present invention has a structure in which a large number of stud dowels 11 are previously planted on the substrate 10 in place of the anchor bolts 1 placed on the inner surface of the conventional opening. Therefore, even when the base plate 10 is attached with anchor bolts 13, for example, the anchor bolts 13 may be of a very small number that can support the base plate 10, and the anchor bolts compared to the conventional case. Can be reduced as much as possible. In addition, since the stud dowel can be planted on the substrate 10 at a factory, the stud dowel can be easily and straightly arranged at a predetermined pitch. As a result, there is no hassle of placing a large number of anchor bolts 1 as in the prior art, and the construction state with high reliability, that is, the integrity of the existing structure and the brace 2 is high while greatly reducing the work on site. Construction is possible.
[0017]
In addition, since the anchor bolt 13 for attaching the above-mentioned substrate may be driven with a wide pitch (interval), when hitting an existing reinforcing bar in the housing when drilling for anchor bolt placement, Or when there is a possibility of hitting, the placement position can be easily changed.
[0018]
Further, since the number of anchor bolts to be installed is small as described above, the generation of noise, vibration, dust and the like is small, and it is possible to perform the construction while using the existing structure. When it is fixed to the inner surface of the opening only with an adhesive, drilling work is not required, and noise, vibration, dust generation, etc. are reduced, and it is also good for repair work such as hospitals, school buildings or government buildings. There are effects such as being applicable.
[Brief description of the drawings]
FIG. 1 is a front view showing a construction example of a seismic repair method for an existing structure according to the present invention.
FIG. 2 is an enlarged view of a part of the construction example.
3A and 3B are cross-sectional views taken along lines AA and BB in FIG. 2, respectively.
FIG. 4 is an explanatory view showing a construction procedure of an earthquake-proof repair method for an existing structure according to the present invention.
FIG. 5 is a front view showing an example of a conventional earthquake-resistant repair method for an existing structure.
FIG. 6 is an enlarged view of a part of the conventional example.
7 is a sectional view taken along line CC in FIG. 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Anchor bolt 10 Board | substrate 11 Stud dowel 12 Adhesive 13 Anchor bolt 14 Nut 2 Reinforcing bar 3 Spiral line S Opening

Claims (2)

A substrate made of a channel-shaped steel material in which a number of stud dowels are implanted in the longitudinal direction is arranged and fixed on the inner surface of the opening formed in the existing structure to be seismically strengthened, and a reinforcing bar is arranged in the opening, and the reinforcing bar Inserting a spiral bar for preventing bearing failure at the position of the connecting part with the frame at the periphery of the opening of the opening, and placing concrete in the opening so as to embed the spiral bar, the reinforcing bar and the stud gibber, Seismic retrofit method for existing structures, characterized by building walls. The method for seismic retrofit of an existing structure according to claim 1, wherein the substrate is arranged and fixed to the inner surface of the opening by an adhesive or by using an adhesive and an anchor bolt in combination.

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