JPH0578613B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for smoothing the solidified surface of concrete, mortar, etc.

(Prior art) Concrete cast as a building frame, mortar painted on walls, etc., as well as building components made of concrete and mortar, are immediately cleaned of their hardened surfaces, whether using formwork boards or not. It is difficult to obtain it in a smooth state, and many concave holes of various sizes often occur. The causes of this are considered to be residual bubbles on the contact surface of the formwork plate, aggregation of dissolved fine air, bubbles due to vaporization of water, gas generated by reaction, etc., and are almost unavoidable. In addition, cracks are likely to occur in aged concrete. Therefore, not only when concrete, mortar, etc. are to be put to use after hardening, but also when the surface is to be painted, these holes or cracks must be repaired by filling them with filler in advance.

Conventionally, the method of filling these many dents and cracks is to coat the entire surface of concrete, mortar, etc. or just the dents one or more times with fluid concrete, mortar, etc., and then use a roller, trowel, or spatula. A method has been used in which the surface is leveled using a method such as a method of leveling the surface using a method such as a method of leveling the surface by using a method such as a method of smoothing the surface of the surface of the surface, and then scraping off the excess portion.

(Problems to be Solved by the Invention) However, these methods are not preferable because they not only require the effort and waste of painting unnecessary parts, but also change the surface shape, color, etc. of the original concrete, etc. Often there isn't.

The present inventor focused on the above problems and attempted to solve them.

(Means for Solving the Problems) As a result of intensive study on methods for solving the problems of the conventional art, the inventors of the present invention found that after pasting an adhesive thin film made of a heat-melting synthetic resin onto a surface having recessed holes, etc. It was discovered that by heating the adhesive thin film from the outer surface at a temperature at which the thin film can be melted, the thin film in a portion such as a concave hole is melted, opened, and penetrated preferentially than other portions, and the present invention has been achieved. completed.

That is, the gist of the present invention is to provide a method for filling concave holes or cracks formed on the solidified surface of concrete or mortar with uncured concrete, cement mortar, gypsum plaster, etc. After pasting a manufactured thin film and subsequently heating the thin film at a temperature higher than its melting point from the surface of the thin film to produce a through hole in the thin film only in the recessed hole or crack portion, at least the portion of the through hole in the thin film is included. The method of surface treatment of concrete or mortar includes applying uncured concrete, cement mortar, gypsum plaster, etc. to the surface of the thin film, and then peeling off the thin film.

Hereinafter, the content of the present invention will be explained in detail.

The adhesive heat-melting synthetic resin thin film in the present invention includes a synthetic resin thin film coated with an adhesive. Examples of thin films include low, medium or high density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride,
Materials such as polyester (for example, polyester of ethylene glycol and terephthalic acid), nylon (for example, polyamide of adipic acid and hexamethylene diamine) are used.

Although these thin films may be unstretched, it is more preferable that they be stretched and easily shrink when heated.

The type of adhesive material is not particularly limited;
It is sufficient if the surface of concrete, mortar, etc. is adhesive, and rubber-based adhesives are a typical example.
In this case, materials that harden early after adhesion are not preferred. Non-hardening materials are easy to handle.

Other examples of the adhesive heat-melting synthetic resin thin film used in the present invention include a thin film obtained by coating a synthetic resin paint with film-forming properties,
This paint may be emulsion-resistant, solvent-based, or any other type.

This paint is applied to the surface of concrete, mortar, etc. and dried to form a peelable thin film that adheres to the surface.

Raw material resins for paint include polyvinyl acetate,
Ethylene-vinyl acetate copolymer, styrene-(meth)acrylate copolymer, ethylene-
(Meth)acrylic acid ester copolymers, etc.

As one of the methods according to the present invention, concrete,
When applying a thin film coated with an adhesive material to a hardened surface such as mortar, it must be adhered tightly so that no air bubbles are formed in areas other than the concave holes. In order to do this, it is preferable to attach the thin films one after another starting from one end. To make such application effective, a smooth rubber roller may be used. That is, when such a roller is used, even if the cured surface has undulations or small protrusions, the adhesive thin film can be applied uniformly over the entire area without entraining air because it deforms to accommodate them. However, the invention is not limited to the use of rubber rollers. When the adhesive thin film is applied uniformly using the above method, air remains only in the pores formed on the hardened surface of concrete or mortar.

On the other hand, when the above-mentioned paint is used instead of the adhesive thin film, it is applied to the entire hardened surface of concrete or the like by brush coating, roll coating, etc., and dries to form a film. In this case, the paint typically does not flow into the pores of the cured surface. Therefore, even when this method is used, air remains only in the concave portions of the hardened surface of concrete, etc., and the thin film is raised only in these portions.

When heat having a temperature higher than the melting point of the synthetic resin is applied from the outside to the synthetic resin thin film pasted or formed on a hardened surface such as concrete as described above, the area where there is air under the thin film, i.e. The part of the thin film that rises from the hardened surface first melts and opens, the molten resin contracts, and the opening diameter gradually increases until it reaches the outer periphery of the recessed hole and stops there, forming a through hole. Heating is continued or stopped as necessary while observing this state.

Suitable heating methods include a flame treatment method, a high-temperature hot air injection treatment method, and a method of bringing a radiant heat radiator close to the surface and utilizing the heat.

It is difficult to explain the reason why the above-mentioned heating preferentially melts the parts that have risen from the hardened surface and causes them to open (penetrate), but it may be due to the expansion of the air in the recesses or the fact that the parts that are in contact with the thin film melt. It is thought that this may be due to the difference in heating rate due to the difference in heat capacity between air and concrete or mortar.

Next, apply an uncured material such as concrete or cement mortar for treating the recessed holes over the thin film having the through holes formed in this way, including the through holes in the center, and if necessary, apply it under pressure. Fill the concave hole with them. In addition to the above-mentioned fillers, cement paste or mortar containing synthetic resin emulsion, gypsum plaster, cement-based waterproofing materials, and other polymer mortars can be used as fillers.

Immediately after applying and filling the above, leave it for a while.
When the synthetic resin thin film having the through holes is peeled off before or after the filler is cured, the necessary filling coating is applied only to the concave holes. The filled area may be slightly raised in some cases, and the surface may be rough, so use a trowel or similar tool to scrape it off to match the original solidified surface of concrete or mortar. and then leveled.

In this way, only the concave portions are filled with the necessary filling, which is advantageous because there is no double application on the original concrete surface. Examples will be described below.

(Example) Fig. 1 shows the surface condition of concrete 1 after it has been formed by the formwork forming method and the formwork plates have been removed. It looks unsightly.

FIG. 2 shows a partially cutaway sectional view when a stretched polyester thin film 3 (100 μm) coated with a rubber-based adhesive is pasted on this surface. Air 4 remains only in the concave holes 2, 2....

FIG. 3 shows an enlarged view of the surface of the thin film 3 being heated by the flame 5, and the air 4 in the recessed holes 2, 2, . . . gradually melted to form through holes 6, 6, .

Figure 4 shows a state in which the polymer cement mortar 7, 7, etc. for filling treatment is applied only to the part where the through hole is located, but the recessed hole can be easily filled by press-fitting with a trowel (not shown) or the like. It was done.

Figure 5 shows the state after peeling off the thin film 3. The slightly raised fillers 8, 8... are scraped off with a trowel, leaving the original solidified surface 9 as a whole.
became on the same plane as the

Figure 6 shows a thin film 1 on the surface of mortar 1' using ethylene-vinyl acetate copolymer emulsion paint.
This figure corresponds to the above-mentioned FIG. 2, and the mortar was filled by the same operation after heat treatment.

(Effects) According to the method of the present invention, it is possible to easily and uniformly fill only the concave portions of concrete, mortar, etc. that have concave holes on the surface with the filling material, and by the operation, Since no extra coating is applied to the original concrete surface, its shape, surface color, etc. can be maintained as is.

[Brief explanation of the drawing]

Figure 1 shows concrete that has been formed in a formwork.
The figure shows a cross-sectional view of the state in which a thin film of meltable synthetic resin coated with adhesive is pasted on this surface, Figure 3 shows a cross-sectional view of the flame treatment state and the state in which melted through-holes are generated, and Figure 4 shows the through-hole area. FIG. 5 shows a cross-sectional view after the thin film is peeled off, and FIG. 6 shows a cross-sectional view when the thin film is formed by the coating method. Next, the symbols used in the drawings will be explained. 1,
1'... Concrete formed by formwork, 2... Recessed hole, 3... Adhesive coated polyester thin film, 4...
Air, 5... Flame, 6... Melting through hole, 7, 8...
... Polymer cement mortar for filling treatment (filling material), 9 ... Original solidified surface, 10 ... Thin film formed by paint application.

Claims (1)

[Claims] 1. In a method of filling concave holes or cracks formed on the solidified surface of concrete or cement mortar with uncured concrete, cement mortar, gypsum plaster, etc., a thin film made of adhesive heat-melting synthetic resin is pasted on the solidified surface, Subsequently, the thin film is heated from its surface to a temperature higher than its melting point to form through holes in the thin film only in the concave holes or crack portions, and then uncured concrete is applied to the surface of the thin film, including at least the portions of the through holes. A method for surface treatment of concrete or mortar, which comprises applying cement mortar, gypsum plaster, etc., and then peeling off the thin film.