JPH10102686A - Thick slate and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of efficiently manufacturing a thick slate which is light in weight, low in heat conductivity and excellent in bending strength and rigidity and whose surface can easily be painted. SOLUTION: Mortar 2 forming a thick slate 1 is mixed with at least 5-25wt% of fly ash to cement and 3-12wt% of silica fume to cement, and glass fiber 3 of length of 50-200% for thickness of the thick slate is mixed with e.g. broken material 4 of light-weight cellular concrete in which the residue produced during factory production of an ALC made wall plate is finely broken.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thick slate such as a roof tile and a method for producing the same.

[0002]

2. Description of the Related Art Thick slate such as roof tiles is generally formed by pressing mortar obtained by kneading Portland cement, natural sand and water at a fixed ratio at a high pressure of 50 kgf / cm ² or more, drying and curing. Has formed.

[0003]

However, in the case of the above-mentioned thick slate, in order to obtain sufficient bending strength as a tile, the thickness must be made sufficiently thick, so that the weight becomes heavy. For example, there is a problem that workability when roofing a tile is deteriorated, and that the weight on the roof increases, which adversely affects the strength of the building.

[0004] On the other hand, a slate in which the strength is enhanced by mixing glass fiber or the like into cement is also performed. However, if a reinforcing material such as glass fiber is mixed, the fluidity of the mortar deteriorates. Therefore, the mortar does not spread to the end during molding. In particular, in order to enhance the cosmetic properties, fine irregularities are formed on the surface of the thick slate. However, it is difficult to form such irregularities if the fluidity is poor. Furthermore, in order to obtain sufficient bending strength, the reinforcing material needs to be dispersed parallel to the plane direction of the slate, but as described above, if the fluidity of the mortar is poor, there is a problem in the dispersibility of the reinforcing material. is there.

[0005] In addition, this type of thick slate is generally coated with a paint on its surface in order to enhance the decorativeness. However, in the case of a conventional mortar, the mortar released during the hydration process of the cement is used. There is also a problem that the surface pH is increased by the influence of calcium, and the coating conditions are very poor. The present invention has been developed in view of the above circumstances, and aims to be excellent in bending strength and rigidity, can be easily painted, yet light weight and low thermal conductivity thick slate, It is another object of the present invention to provide a manufacturing method capable of efficiently manufacturing such a thick slate.

[0006]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 is directed to a thick slate formed by compression molding a mortar mainly composed of cement and curing it. The mortar contains at least 5 to 25% by weight of fly ash and 3 to 12% by weight of silica fume with respect to cement, and 50 to 200% of the thickness of crushed lightweight cellular concrete and thick slate. The gist of the present invention is a thick slate obtained by mixing glass fibers having a length.
In order to obtain the above thick slate, a mortar in which a desired amount of cement, fly ash, silica fume, glass fiber and crushed material of lightweight cellular concrete are mixed is desirably placed on a lower mold having a surface covered with a dewatering cloth. The gist is a method of manufacturing a thick slate in which a large amount of slate is placed and press-formed by an upper die.

[0007]

According to the first aspect of the present invention,
Since the mortar for forming the slate has increased fluidity due to the mixed fly ash and silica fume, the mortar spreads smoothly to every corner of the mold during compression molding of the mortar, and the crushed material of lightweight cellular concrete is evenly distributed. Along with dispersing, very fine silica fume of particles gathers on the surface of the raw thick slate by riding on the moisture due to the discharge of water by the above-mentioned compression, and further, during the compression, the compressed mortar is in the mold. As the glass fiber in the mortar is spread, the glass fiber in the mortar also disperses in a direction perpendicular to the thickness direction of the slate, that is, in a state parallel to the plane direction of the slate, along with the movement of the mortar. In the mold slate, the glass fiber is oriented two-dimensionally and has high bending strength, but the mixture of crushed lightweight cellular concrete Therefore, the weight of the slate is also light and the thermal conductivity is low, for example, the workability when roofing the tiles is good, the weight on the roof is also light, the heat insulation is also excellent, and Since the glass fiber and the crushed product of the lightweight cellular concrete are wrapped by silica fume particles and held together, the rigidity of the slate is high, and for example, it is possible to suppress the occurrence of cracks during transportation or the like. .

In the thick slate according to the first aspect of the present invention, silica fume collects on the surface of the slate and the surface becomes dense, and the silicic acid in the silica fume is reduced to the hydroxyl group of calcium hydroxide in the cement. And lowers the pH value, thereby improving the adhesion of the paint to the surface of the thick slate, and making the paint beautiful.

According to the first aspect of the present invention, the crushed lightweight cellular concrete is used.
For example, it is possible to recycle such residues by using finely crushed residues generated when an ALC wall plate used as a wall surface of a house is produced in a factory. According to the invention as set forth in claim 2, while the water in the mortar is dehydrated by the press and the malleability of the mortar is improved by the silica fume, the crushed material of the lightweight cellular concrete is evenly dispersed, Further, the desired slate can be efficiently produced by uniformly dispersing and orienting the glass fibers in the plane direction of the slate roof tile.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a state in which a thick slate 1 according to the present invention is viewed from obliquely above with a part cut away. Mortar 2 is compression molded into a predetermined shape and cured and cured. The mortar 2 forming the slate 1 is obtained by mixing fly ash and silica fume as admixtures with cement as a main material, mixing glass fibers 3 and crushed material 4 of lightweight cellular concrete, and kneading with water. In the cement, 5 to 2% by weight of fly ash and 3 to 12% by weight of silica fume are mixed with cement.

[0011] In addition, fly ash is
If the amount is less than 25% by weight, the effect on the fluidity of the mortar and the strength of the mortar is reduced, but if it exceeds 25% by weight, no further effect can be expected. Further, if the silica fume is less than 3% by weight of the cement, the effect of lowering the pH and the effect of densification cannot be obtained, and if it exceeds 12% by weight, the mortar becomes a paste and the releasability from the mold becomes poor. It becomes worse and it is not possible to obtain a molded article having excellent design properties.

The glass fiber 3 has a length of 50 to 200% of the thickness of the thick slate 1. The glass fiber 3 is made of alkali-resistant E glass. preferable. If the length of the glass fiber 3 is less than 50% of the thickness of the thick slate, the effect as a reinforcing material is almost lost. Also, if it exceeds 200%,
Some do not orient in the plane direction during compression molding.

The crushed material 4 of lightweight cellular concrete is produced, for example, as a wall surface of a house, and is generally A
LC (autoclaved lightweight)
A predetermined amount of finely crushed lightweight cellular concrete called "concrete" is mixed.
In the embodiment, the above-mentioned industrial waste is reused by using finely crushed residue generated when an ALC wall plate used mainly as a wall surface of a house is produced in a factory as the above lightweight cellular concrete. I'm trying.

The above-mentioned crushed product of lightweight cellular concrete 4
Is preferably mixed with the above-mentioned fly ash and cement made by mixing silica fume in an amount of 30 to 60% by weight, and in the embodiment, 40% by weight. The crushed material 4 preferably has a particle size of 0.5 mm to 3 mm, and in the embodiment, has a size of 2 mm.

Next, a method of manufacturing the thick slate 1 according to the present invention will be described in the order of steps. [First process] Cement, fly ash, silica fume, glass fiber 3 and crushed product of lightweight cellular concrete 4
Is kneaded with water in a kneading apparatus to form a mortar 2. As the kneading apparatus, it is preferable to use one as described in Japanese Utility Model Application No. 62-196344 devised by the same applicant of the present invention. The kneading apparatus according to the present invention is provided with a stirring chamber, a shaft provided in the shaft of the stirring chamber, a drive shaft that is rotationally driven by external power, and rotates with the drive shaft,
The kneaded material is provided with a cylindrical stirring roller that rolls while abutting the side peripheral surface thereof on the bottom surface of the stirring chamber and crushes the kneaded material with the bottom surface, and a plurality of the plurality of rollers are provided on the side peripheral surface of the roller. Since the ridges are formed in parallel, the contact area between the roller and the bottom surface of the stirring chamber is larger than that of a conventional roller. Therefore, the rollers roll without stopping and crush while squeezing the mortar, whereby the glass fibers in the mortar can be uniformly dispersed in a short time. The glass fibers used in the thick slate according to the present invention are tens to hundreds of bundles, and the bundles are loosened and dispersed during kneading, but the kneading time is long. In addition, the glass fiber is scratched during kneading, which leads to a decrease in bending strength of the product. Therefore, it is preferable to use the kneading device of the present invention. [Second step] The mortar 2 prepared in the first step is sent to a measuring tank by a conveyor such as a conveyor, measured in a desired amount, dropped into a lower mold, and then covered with an upper mold. Compression molding the mortar.

It is preferable that the mortar 2 is stirred before it is lightened in the measuring tank. In the lower mold, a dewatering sheet is placed on a wire mesh, and the mortar 2 is dropped on the dewatering sheet. Therefore, the water in the mortar 2 is squeezed through the wire mesh by the compression, and a predetermined The raw thick slate 1 containing is formed. By the way, the mortar 2 has increased fluidity due to the mixed fly ash and silica fume. Therefore, at the time of the compression molding of the mortar 2 in the second step, the mortar 2 spreads smoothly to every corner of the mold, and the The crushed material 4 is also dispersed uniformly, and the very fine silica fume of the particles is liable to collect on the surface of the raw thick slate 1 on the water due to the discharge of the water by the above-described compression. As the compressed mortar 2 is expanded in the mold, the glass fibers 3 in the mortar 2
Is dispersed in a direction perpendicular to the thickness direction of the slate 1, that is, parallel to the surface direction of the slate 1. [Third Step] The raw thick slate 1 prepared in the second step is put in a curing room, and the curing room is heated at 70 ° C. to 80 ° C. for a predetermined time.
After being kept in a steam atmosphere at a temperature of ° C., it is left in a closed curing room for a predetermined time to cure and harden, thereby completing the thick slate 1.

The surface of the completed thick slate 1 is coated as necessary. The coating method is not particularly limited, but spray coating with a spray is preferable because the coating can be performed evenly. By the way, in the thick slate 1 of the present invention, as described above, silica fumes are gathered on the surface of the slate 1 and the surface is dense, and the silicic acid in the silica fume reduces the calcium hydroxide in the cement. Since it reacts with a hydroxyl group to lower the pH value, the adhesion of the paint to the surface of the thick slate 1 is improved, and the paint can be finely performed.

Thus, the above-mentioned thick slate 1 has a high bending strength due to the two-dimensional orientation of the glass fibers 3 and, at the same time, the crushed material 4 of lightweight cellular concrete is mixed therein. The weight is light, the thermal conductivity is low, the workability of roofing the slate 1 on the roof is good, the weight on the roof is light, and the heat insulation is excellent. In addition, the glass fiber 3 and the crushed material 4 of the lightweight cellular concrete are wrapped by silica fume particles and are connected to each other, so that the rigidity of the slate 1 is sufficiently increased, and for example, cracks are generated in the slate 1 during transportation. Can be suppressed.

Further, in the above embodiment, the crushed material 4 of the lightweight cellular concrete mixed into the mortar 2 is obtained by finely crushing the residue generated during the factory production of the ALC wall plate used as the wall surface of the house. Since such waste is used, recycling of such residue can be achieved. In the above embodiment, as the crushed material 4 of lightweight cellular concrete, AL
The residue generated when the C wallboard is produced at the factory is finely pulverized, but the present invention is not limited to this.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a thick slate according to the present invention with a part cut away.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Thick slate 2 Mortar 3 Glass fiber 4 Crushed lightweight cellular concrete

Claims (2)

[Claims] In a thick slate formed by compression-molding and curing and curing a mortar mainly composed of cement, the mortar contains at least 5 to 25% by weight of fly ash and 3% of silica fume based on cement. ~
12% by weight and 50 to 200 with respect to the thickness of the crushed material of lightweight cellular concrete and thick slate.
A thick slate comprising a mixture of glass fibers having a length of 10%. 2. In obtaining the slate according to claim 1,
A desired amount of mortar, which is a mixture of cement, fly ash, silica fume, glass fiber, and crushed material of lightweight cellular concrete, is placed in a desired amount on a lower mold having a surface covered with a dewatering cloth, and pressed by the upper mold. A method for producing a thick slate, which comprises molding.