JP2707905B2 - Concrete surface treatment method and formwork used in the method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating the surface of concrete, which protects the surface of a concrete product from air pollution and salt damage and imparts an aesthetic appearance by coloring, and a mold used in the method.

[0002]

2. Description of the Related Art As a method of protecting the surface of a concrete product from air pollution and salt damage in the atmosphere and giving it an aesthetic appearance, a method of coating the surface of a concrete product with a resin is known. In this case, the concrete product can be colored by adding a pigment to the coating resin.

[0003] In the method of coating a resin on the surface of a concrete product, there is a problem in the durability of the resin itself, such as the resin peeling off from the concrete, and the coating cannot be performed until the concrete is sufficiently dried. The trouble of painting after molding and preparation thereof has been complicated.

On the other hand, by molding a concrete product using colored concrete in which an inorganic pigment is dispersed in white cement, it is possible to solve various problems caused by painting.

[0005]

However, when a concrete product is molded using colored concrete, there is an uneconomical aspect such as coloring the entire surface, irrespective of the fact that only the surface needs to be colored. It is impractical to make the small area region of different colors different in process.

The method of the present invention solves the above-mentioned drawbacks. An object of the present invention is to form a dense colored protective layer integrally on the surface of a concrete product by chemical bonding at the same time as molding the concrete, thereby making the surface of the concrete product robust. An object of the present invention is to provide a concrete surface treatment method and a formwork used for the method, which can protect the condition and at the same time impart an aesthetic appearance.

[0007]

In order to achieve the above object, the present invention provides a method for forming a non-hydraulic, alkali-reactive particle component and a coloring pigment on the inner surface of a concrete casting mold. By forming an inorganic coating film containing and casting concrete inside the formwork, the particle components in the coating film are chemically reacted with each other and cured, and are integrally bonded to the concrete surface. is there.

Another aspect of the present invention is a mold for casting concrete, wherein an inorganic material containing a non-hydraulic, alkali-reactive particle component and a coloring pigment is provided on the inner surface of the mold. It is formed by forming a coating film.

[0009]

[Function] When concrete is poured into a formwork, the non-hydraulic and alkali-reactive particle components in the coating film react and harden under the presence of alkali components contained in the excess water of concrete, and the concrete surface is hardened. Then, a dense coating layer in a state where the coloring pigment is dispersed is formed integrally therewith.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. 1 (a) to 1 (c) show a molding procedure according to the method of the present invention. First, as shown in FIG. 1 (a), a non-hydraulic and alkali-reactive inorganic coating film 2 is applied to a predetermined thickness on the inner surface of a mold 1, that is, on a concrete casting side, and dried.

The coating film 2 is composed of a non-hydraulic and alkali-reactive particle component composed of a latent hydraulic substance represented by slag powder and a pozzolan reactant represented by fly ash powder and silica fume powder alone or in a mixture. In addition, 3 to 5% by weight of an inorganic pigment for concrete (coloring pigment) is blended with the particle component, and a water-soluble resin such as polyvinyl alcohol is used as a binder and these are dispersed and mixed in water as a solvent.

Therefore, the inorganic coating film 2 is in the form of a liquid having a predetermined viscosity, and can be handled in the same manner as a coating material. The coating method for the mold 1 is almost the same as the coating method.

The particles of the above-mentioned particle components are fine, and when they are cured, they form a dense layer. However, they do not react with water or moisture and are cured by themselves. It is the first time that a curing reaction occurs. And
When the water content evaporates due to drying after the application, as shown in an enlarged part of FIG.
And the pigment 2c is made up of the particle component 2a
And is bound to the water-soluble resin 2b in a state of being uniformly dispersed as appropriate, and becomes a colored porous film which is adhered and held on the inner surface of the mold 1.

After the above operation, concrete 3 is cast on the inner surface of the formwork 1 as shown in FIG. In the surplus water W in the concrete 3, hydroxide lime: Ca (OH) ₂
Is contained in a large amount, and excess water W is discharged from the surface as the concrete 3 hardens, exuding into the inside of the inorganic coating film 2 and sequentially dissolving the water-soluble resin 2b. As shown in an enlarged manner, the surplus water W is composed of the particle component 2a.
And contact each other while passing between the pigment and the pigment 2c.

As a result, the particle component 2a reacts with each other in the presence of calcium hydroxide (Ca (OH) ₂ ) contained in the surplus water W to form insoluble inorganic salts, and the pigment 2c is dispersed. At the same time, the particle component 2a located at the interface with the concrete 3 is integrated with the surface of the concrete 3 by a chemical reaction.

Accordingly, when the concrete 3 is removed from the mold after curing, as shown in a schematic cross section in FIG. 1 (c), the surface of the concrete 3 has a cured particle component 2a and a pigment 2c dispersed between them. The concrete 3 is protected from acid and salt damage by this coating layer, and is given an aesthetic appearance corresponding to the coloring. The thickness of the inorganic coating film 2 can be appropriately set according to the thickness required after curing and the economic efficiency. In addition, by forming an inorganic coating film having different coloring according to the partial region of the mold 1,
The color scheme can be varied.

FIG. 2 shows another embodiment of the present invention, in which a water-permeable sheet 4 is interposed between a mold 1 and an inorganic coating film 2. The water permeable sheet 4 is generally used to promote the discharge of surplus water. Therefore, in this embodiment, the surplus water discharged from the surface of the concrete 3 passes through the inorganic coating film 2 and is forcibly discharged out of the mold through the water-permeable sheet 4. At the same time as the coloring is achieved, the contact of the surplus water with the particle component 2a is forcibly performed.
a) further promotes the chemical reaction of water-soluble resin 2b
Can also be dissolved and discharged.

[0018]

As described in detail in each of the above embodiments, the concrete surface treatment method and the formwork used in the method according to the present invention have the same effect as the concrete pouring and the coating method. Hydraulic and alkali-reactive particle components react and cure under the conditions of the presence of alkali components contained in the excess water of concrete, and a dense coating layer in which the coloring pigment is dispersed integrally with the concrete surface. Is formed, and the durability and durability are remarkably improved as compared with conventional coating means and the like, and durability and aesthetic appearance can be simultaneously imparted to the concrete surface.

Further, since only the surface is covered with the dense coating layer, it is much more economical than the case where the whole concrete is formed by colored concrete. Can be easily applied, and various colors can be applied by changing the color of the pigment depending on the portion of the mold.

[Brief description of the drawings]

FIG. 1A is an explanatory sectional view showing a state where an inorganic coating film is applied to a mold. (B) is an explanatory sectional view showing a concrete casting state. (C) is a schematic cross-sectional explanatory view showing a surface portion of the concrete after demolding.

FIG. 2 is an explanatory sectional view showing another embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 mold 2 inorganic coating 2a particle component 2b water-soluble resin 2c inorganic pigment 3 concrete

Claims (2)

(57) [Claims] 1. An inorganic coating film containing a non-hydraulic, alkali-reactive particle component and a coloring pigment is formed on an inner surface of a concrete casting mold in advance, and the inside of the mold is formed. A concrete surface treatment method, wherein concrete is cast to cause the particle components in the coating film to chemically react with each other to be hardened and to be integrally bonded to the concrete surface. 2. A mold for casting concrete, wherein an inorganic coating film containing a non-hydraulic, alkali-reactive particle component and a coloring pigment is provided on an inner surface of the mold. A formwork characterized by being formed.