JPH0140793B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to highly weather-resistant concrete shaped building materials such as concrete plates, slate plates, and concrete blocks, which are made by mixing and molding a building material shaping binder such as cement or gypsum. .

[Conventional technology]

In recent years, concrete building materials such as AE concrete or ALC concrete, and various lightweight concrete shaped building materials mixed with binders other than cement, such as gypsum, have come to be widely used as building materials such as concrete panels or concrete blocks.

However, these lightweight concrete shaped building materials
Because it is porous and hygroscopic, even after construction, the amount of moisture it contains changes due to changes in the weather, which has a significant impact on its strength and lifespan over many years of use. Especially in cold weather,
Repeated freezing and thawing of internal moisture due to temperature changes often causes cracks and failures in concrete products. Furthermore, absorption of corrosive moisture corrodes the concrete itself, causing a decrease in strength and staining of the external surface.

In order to prevent deterioration and staining of such concrete building materials due to moisture absorption, protective treatments such as painting are carried out, but the paint itself does not have sufficient weather resistance and moisture resistance, and the purpose has not been fully achieved. .

Furthermore, Japanese Patent Publication No. 57-31472 discloses that metal thermal spraying is applied to the coating base in order to improve the corrosion resistance of concrete shaped building materials by such coating.

The formation of this metal sprayed film improves the adhesion of the paint itself to the sprayed film surface, but there are problems with the adhesion between the concrete base and the metal sprayed film, and the thermal expansion of the concrete and metal Due to the difference in rate, there are problems such as peeling during use.

[Problem to be solved by the invention]

The problem to be solved by the present invention is to eliminate the problems caused by the presence of surface pores in concrete, particularly lightweight concrete shaped building materials.

[Means to solve the problem]

The present invention solves the above-mentioned problems by forming a ceramic sprayed coating layer together with a sealing layer on the surface of the concrete shaped building material, and also gives the concrete shaped building material aesthetic properties such as fire resistance and color. It is.

The concrete shaped building materials referred to in the present invention include:
Adding a binder such as cement or plaster to the material,
Furthermore, if necessary, various fibers can be mixed and kneaded and applied to building materials formed by casting.

The thickness of the sprayed coating is generally 150 μm or less, preferably 80 to 100 μm, so that the intended use as a building material can be fully achieved.

In addition, the ceramic material forming the thermal spray coating layer in the present invention includes ceramics such as Al ₂ O ₃ and SiO ₂ , or ceramics containing glass-forming components such as B ₂ O ₃ and Na ₂ O. use.

In the case of ceramic alone, it is preferable to apply an inorganic sealant such as ZrO ₂ /SiO ₂ based sealant or an organic sealant such as polyurethane resin to the surface of the concrete substrate or the surface of the ceramic sprayed coating.

Furthermore, when the thermal spray coating contains glass, the thermal spray particles fuse with each other in the coating layer and are formed in a non-porous state, so there is no need to form a sealing layer.

In the present invention, the sealing film does not necessarily need to be formed from the outer surface of the thermally sprayed coating in a post-processing manner, but a precoat of a sealing agent is formed on the cleaned surface, and then a thermally sprayed coating is formed from this precoated surface. You can also.

Also, for example, Al ₂ O ₃ , SiO ₂ , TiO ₂ , Na ₂ O,
When forming a thermal spray coating by thermally spraying a glass-forming thermal spray material containing B ₂ O ₃ as a main component, the substrate is heated in advance to a temperature suitable for forming a glass coating. The sprayed particles can be fused together on the substrate surface to form a sprayed coating that has the same effect as hole sealing.

[Effect]

When these ceramic materials form a sprayed coating, they have good wettability with the concrete material, have good pore-sealing properties to the concrete base material, and form a sprayed coating with excellent adhesion to the concrete base material. be able to.

Further, since these ceramic materials have a coefficient of thermal expansion and a coefficient of thermal contraction similar to those of the concrete base material, the formed coating will not peel off.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the following, embodiments of the present invention will be explained with reference to the accompanying drawings.

1 is a panel obtained by mixing and kneading sand, slag grains, or ceramic product grains as aggregate with a binder such as cement, and molding the mixture, and actively forming aerated concrete by performing steam curing during curing of the molded object. After curing and solidifying, it was dried, and the roughness of the pattern was adjusted and the surface was purified.

A 100 μm thick ceramic spray coating 2 of white alumina was applied to the same surface using a plasma spray gun while maintaining the concrete surface temperature at 150°C.

This thermal sprayed coating 2 alone had good adhesion to the concrete base 1 when used with ordinary building materials such as ALC concrete plates, but the sealing coating 3 was applied using Snowtex (registered trademark of Nissan Chemical Co., Ltd.). was formed.

The obtained thermal sprayed coating after the sealing treatment did not peel off even in an autoclave environment and had excellent weather resistance.

〔Effect of the invention〕

The highly weather resistant concrete shaped building material of the present invention can provide the following effects.

(1) The formed thermal spray coating has good compatibility with the concrete base, so it does not peel off, and there is no absorption of atmospheric moisture or rainwater into the pores of the concrete.

(2) Therefore, there is no occurrence of breakage due to freezing due to a drop in temperature, and excellent durability can be obtained especially when used in cold regions.

(3) Excellent corrosion resistance can be obtained even in corrosive environments.

[Brief explanation of drawings]

The drawing shows a cross-sectional view of an example of a highly weather resistant concrete shaped building material. In the figure, 1: substrate, 2: thermal spray coating, 3: sealing coating.

[Claims]

1. A method for regenerating a concrete layer of a concrete structure, comprising separately applying a saturated calcium hydroxide aqueous solution and a colloidal silica solution, and then applying a modified silica gel paint.