JP3953198B2 - Reinforcing structure and reinforcing method of building - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reinforcing structure of an existing building that is seismically reinforced by, for example, a seismic reinforcing work for a building.
[0002]
[Prior art]
As a method for reinforcing seismic reinforcement of buildings, there is a method of arranging a frame body through a form frame in a frame surrounded by columns and beams of an existing building. As this method, for example, a steel mold and a frame are fixed, and then placed in a frame surrounded by pillars and beams of a building, and a space between the frame, the mold and the frame is filled with a curable material. A method of filling the material can be mentioned. At this time, a steel mold is usually used as the mold.
As a method for fixing the steel mold and the frame, conventionally, a method of fixing by welding such as spot welding has been used.
[0003]
[Problems to be solved by the invention]
However, when welding, it is necessary to bring a welding machine to the site, and it is necessary to secure a skilled welder, and there is a problem that workability is difficult. Therefore, there has been a demand for a method for reinforcing buildings that can be easily done by anyone.
[0004]
The inventor of the present invention has been made in view of such circumstances, and has found that if a formwork and a frame are fixed with an adhesive, a building can be easily reinforced without special technical skills.
[0005]
[Means for Solving the Problems]
That is, in the present invention, a frame is arranged inside a frame surrounded by pillars and beams of a building via a mold, and a curable filler is injected into the gap between the frame, the mold, and the frame. A structure reinforcement structure for a building, wherein the formwork and the frame body are fixed with an adhesive, and the structure is a reinforcement structure for a building in which the adhesive is an acrylic adhesive. Is a reinforcing structure of the building to which braces are attached, and the reinforcing structure of the building in which the curable filler is a non-shrink mortar. Then, fix the formwork to the frame with acrylic adhesive , place it in the frame surrounded by the pillars and beams of the building, and inject the curable filler into the gap between the frame, the formwork, and the frame. This is a method for reinforcing a building, characterized by
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described below.
[0007]
FIG. 1 shows a frame placed inside a frame surrounded by pillars and beams of a building via a formwork. As the frame, it is preferable to arrange a frame body on a frame surrounded by columns and beams in terms of seismic reinforcement.
In addition to columns and beams, a frame body may be arranged inside a frame surrounded by walls, a ceiling, and a floor.
[0008]
First, the frame 1 and the mold 2 are bonded and fixed with an adhesive (not shown in FIG. 1). In FIG. 1, the mold frame 2 is installed outside the frame body 1, but the mold frame 2 may be installed inside the frame body 1.
[0009]
As the frame 1, one assembled along the pillars and beams of a building, for example, a rectangular one or the like is used. The frame body 1 is preferably a frame body with braces to which a brace is attached in terms of a large seismic reinforcement effect. The brace is an oblique material used for maintaining the structure of the frame body and considering the earthquake-resistant structure, and is attached to the inside of the frame body 1 main body. Examples of braces include Y-type and K-type.
As a material for the braces and the frame, it is preferable to use a steel frame in terms of strength. As the frame, H-shaped steel is preferable in that it can be easily filled with a curable filler described later. The formwork may be a plate-like material, and it is preferable to use a steel formwork as a material of the formwork because of its robustness. A steel mold having a thickness of 2 to 4 cm is usually used.
From the viewpoint of improving the adhesiveness of the acrylic adhesive, it is preferable to remove in advance a coating film such as a rust preventive agent, rust, or black skin, etc. in the marginal portion of the steel mold frame and the steel frame by sanding or the like.
[0010]
As a fixing method, a method of applying an adhesive to one or both of the bonding surfaces of the frame 1 and the mold 2 and bonding them is used.
[0011]
Examples of the adhesive include acrylic adhesives, epoxy adhesives, urethane adhesives, and the like, but particularly excellent in adhesive strength with metals and can be applied in a short time, for example, at a room temperature of −10 ° C. to 40 ° C. Acrylic adhesives are preferred in that they can be cured quickly at low temperatures, the viscosity can be adjusted as low as 5,000 cps or less, and they can be sufficiently filled into the gaps since they do not rapidly thicken even at low temperatures. In addition, the acrylic adhesive can use a simple applicator or mixer, and can easily perform on-site work.
[0012]
An acrylic adhesive refers to an adhesive containing an acrylic monomer.
[0013]
As acrylic monomers, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2 -Hydroxypropyl (meth) acrylate, dicyclopentenyloxyalkyl (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, dimethylaminoethyl (meth) acrylate, polyethylene glycol di (meth) acrylate, 1, Examples include 4-butanediol (meth) acrylate, epoxy (meth) acrylate, trimethylolpropane tri (meth) acrylate, and terminal (meth) acryl-modified liquid polybutadiene. That. These can be used alone or in combination of two or more.
[0014]
Acrylic adhesives can be used in combination with acrylic monomers and other radical polymerizable monomers, but there are no particular restrictions on the other monomers used here, styrene, acrylonitrile, vinyl acetate Monofunctional monomers such as acrylamide and polyfunctional monomers such as divinylbenzene, triallyl cyanurate and triallyl isocyanurate can be used alone or in combination of two or more.
[0015]
The acrylic adhesive used in the present invention is preferably an acrylic adhesive that promotes curing by substantially mixing a polymerization initiator and a decomposition accelerator. As is well-known, curing of acrylic adhesive proceeds by thermal polymerization without adding a curing agent, but when curing acrylic adhesive at civil engineering construction sites, it is stable unlike chemical factories. It is difficult to secure and manage the heat source, and it is necessary to advance the curing reaction by a simpler method. For this purpose, it is preferable to proceed the curing at room temperature by mixing a polymerization initiator and a decomposition accelerator.
[0016]
As the polymerization initiator, a peroxide or an azo compound that is used as a radical polymerization initiator is preferably used. However, the type of the peroxide or azo compound is not particularly limited, and examples of the peroxide include cumene. There are organic peroxides such as hydroperoxide, methyl ethyl ketone peroxide and benzoyl peroxide, and inorganic peroxides such as potassium persulfate and ammonium persulfate, and azo compounds include azobisisobutyronitrile. Among these, organic peroxides are preferable from the viewpoint of curability.
[0017]
The decomposition accelerator is a compound that accelerates the decomposition of the polymerization initiator. Specific examples include thiourea derivatives such as diethylthiourea, amines such as N, N-diethyl-p-toluidine, cobalt naphthenate, cobalt octylate. Organic acid metal salts such as copper acetylacetonate and the like, and these can be used alone or in combination of two or more. Of these, organic acid metal salts and organic metal chelate compounds are preferred from the viewpoint of curability.
[0018]
Among acrylic adhesives, a two-component room temperature curable acrylic adhesive is preferable because the viscosity can be adjusted low and injection can be completed in a short time. The two-component room-temperature curable acrylic adhesive refers to an acrylic adhesive that is divided into two liquids of an A agent and a B agent, the A agent containing a polymerization initiator, and the B agent containing a curing accelerator. Two-component room-temperature curable acrylic adhesive does not require precise adjustment of the mixing ratio of agent A and agent B, and is easy to use with a simple coating machine or mixer because it has high adhesion even with simple mixing. Can work on.
[0019]
If the adhesive has a margin of 3 cm or more, the curable filler can be filled within about 1 hour after fixing, and even if the curable filler is filled, the curable filler does not leak from the adhesive surface.
[0020]
Next, the frame body 1 to which the formwork 2 is fixed is carried and arranged inside the frame 3 surrounded by the pillars and beams of the building. It is necessary to temporarily fix the frame 1 and the frame 3 until the adhesive is cured. Although the method of temporary fixing is not limited, there is a method of using jigs such as a giant clam vise, an L clamp, a magnet, and a bolt.
[0021]
After the adhesive is cured, a curable filler 4 is filled in the gap between the frame 3, the steel mold 2, and the frame 1.
When the frame 1 is H-shaped steel, the curable filler 4 is filled in the space surrounded by the surface of the frame 3, the web of the frame 1, the flanges on both sides thereof, and the mold 2.
[0022]
Although there is no restriction | limiting in particular as a sclerosing | hardenable filler, A super-fast-hardening non-shrink mortar is preferable at the point with big filling property and adhesiveness. The ultra-fast-hardening non-shrink mortar preferably contains a fast-hardening material and an expanding material. Examples of the quick-hardening material include those containing calcium aluminates and gypsum and producing ettringite by a hydration reaction. The expansion material is composed of calcium sulfoaluminate containing free lime and having a mineral composition of 3CaO.Al ₂ O ₃ .Ca ₂ SO _4, and producing ettringite by hydration reaction, or quick lime-based hydration Some produce Ca (OH) ₂ by reaction.
[0023]
Before filling the gap with the curable filler, it is preferable to seal the contact portion between the frame 3 and the mold 2 with the sealing material 5 so that the curable filler does not leak. As the sealing material, a curable filler is preferable.
[0024]
In order to fill the gap with the curable filler, it is preferable to provide holes for injection and air removal in the mold.
[0025]
Furthermore, an anchor may be driven into the frame in order to prevent the mold from being caught by the expansion of the curable filler and to fix the mold to the frame more firmly.
[0026]
【Example】
Example 1
Removes rust-preventive coating to provide a 50mm margin on steel frame 1 (K-type brace with steel frame, frame is made of H-type steel) with a length of 2.5m and a width of 5.5m with a K-type brace attached. To do. Next, a commercially available acrylic adhesive was applied to the margin, and a steel mold 2 having a thickness of 2.3 mm, a width of 230 mm, and a predetermined length was adhered to the steel frame 1.
Thereafter, the steel frame 1 having the steel formwork 2 fixed thereto was temporarily fixed to a frame 3 surrounded by columns and beams of a concrete building by a giant clam vise provided at a pitch of 30 cm. About 1 hour later, the contact portion between the frame 3 and the mold 2 is sealed with the seal material 5, and a commercially available ultrafast hard non-shrink mortar is used as the commercially available curable filler 4 with a pressure of 2 kg / cm ² by a mortar pump. Injected into the gap between the frame 3, the steel mold 2, and the frame 1. The curable filler 4 did not leak from the gap between the frame 3, the steel mold 2, and the frame 1, and the operation was easy and the frame 3 could be reinforced without problems.
[0027]
【The invention's effect】
By the reinforcing structure of the present invention, it has excellent adhesive strength, can be applied in a short time, for example, can be cured at room temperature or low temperature of −10 ° C. to 40 ° C., and can be easily operated, and its industrial utility is extremely large .
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an embodiment of a reinforcing structure for a building according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Frame 2 Form frame 3 Frame 4 Curable filler 5 Sealing material

Claims (4)

A frame is placed inside a frame surrounded by pillars and beams of a building via a mold, and a curable filler is injected into the gap between the frame, the mold, and the frame. A frame reinforcing structure, wherein the frame is fixed with an acrylic adhesive . The reinforcing structure for a building according to claim 1, wherein the frame is attached with braces. The reinforcing structure for a building according to claim 1 or 2, wherein the curable filler is a non-shrink mortar. The frame and formwork are fixed with acrylic adhesive , placed in a frame surrounded by building pillars and beams, and a curable filler is injected into the gap between the frame, formwork, and frame. A method of reinforcing a building characterized by the above.

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