JP2005041195A - Method for production of three-dimensional grc panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently mass-produce a three-dimensional platy GRC panel having projections or recesses in its surface and inner face by surely preventing the bounce of aggregate on a molded face when spraying a mortar to a molding mold. <P>SOLUTION: The production method for the three-dimensional GRC (glass reinforced concrete) platy panel having projections or recesses in its surface and inner face comprises spraying, together with glass fibers, the mortar being a mixture of cement, aggregate and water in the inner face of a three-dimensionally moldable mold from the nozzles under the air pressure of 1-3 kgf/cm<SP>2</SP>, and hardening. In this case, it is preferable to use the lightweight aggregate having the weight per liter of 0.03-0.6 kg and a particle size of ≤3 mm, and also is preferable to use the mortar containing the aggregate in an amount of 8-15 wt% based on the cement. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a three-dimensional GRC panel mainly used for an outer wall of a building.

  A fiber reinforced concrete panel in which glass fiber is embedded in mortar and reinforced with glass fiber is called a GRC panel. This GRC panel is manufactured by adhering mortar with glass fibers embedded in the molding surface of a molding frame. The GRC panel is lighter and stronger than the concrete panel. Taking advantage of this feature, the GRC panel is used as a building outer wall panel. It is used as a particularly large outer wall panel.

Furthermore, as a method for manufacturing the GRC panel, a technique has been developed in which a lightweight aggregate is used for the aggregate to further reduce the overall weight. (See Patent Document 1)
Japanese Patent Laid-Open No. 11-60347

  In the method described in this publication, glass fibers and lightweight mortar are sprayed in a state in which finishing materials such as tiles and stones are arranged at the bottom of the mold, and the finishing materials are embedded on the surface. A planar GRC panel is manufactured. Glass fiber is cut and sprayed onto the formwork from different outlets of the spray gun at the same time as the lightweight mortar. Lightweight mortar is 20-60 wt% lightweight aggregate, 0.1-3 wt% water reducing agent, 0.5-5 wt% shrinkage reducing agent, 0.01-0 .5% by weight thickener, 0.01-0.5% by weight AE agent and 65% by weight or less water are used. The usage-amount of glass fiber shall be 1-10 weight% with respect to mortar.

  This method is characterized in that a light GRC panel can be efficiently manufactured by increasing the amount of light aggregate added. However, this method can efficiently produce a panel having a planar shape as a whole, but it is remarkably effective in producing a GRC panel having a complicated shape such as a three-dimensional plate having convex portions or concave portions on the surface and the inner surface. It takes time and effort. This is because the lightweight aggregate contained in the mortar sprayed on the mold is reflected by the inner surface of the mold and collected at the corner of the mold.

  As shown in FIG. 1, a forming mold 1 for forming a three-dimensional plate-shaped GRC panel in which convex portions or concave portions are formed on the surface and the inner surface without forming the entire shape flat is formed by spraying mortar. A corner portion 2C is formed on the molding surface 2 at the boundary between the rising portion 2A and the horizontal portion 2B. When mortar is sprayed on the inner surface of the molding die 1, the aggregate 4 is reflected by the molding surface 2 as indicated by the arrows and accumulates in the corner portion 2 </ b> C of the molding die 1. The aggregate 4 is reflected because the kinetic energy is large when the aggregate 4 collides with the molding surface 2 and reflects. If mortar is sprayed in a state where a large amount of aggregate is accumulated in the concave portion of the molding die, it becomes impossible to form the projecting portion neatly on the surface. In order to prevent this defect, conventionally, after removing the aggregate accumulated in the recesses, a mortar having a predetermined thickness is preliminarily applied to the inner surface of the recesses of the mold. After applying the mortar, glass fibers and mortar are sprayed on the inner surface of the mortar. This method not only takes time to remove the aggregate and apply the mortar, but also does not produce the whole continuously, so there is a defect that the part where the trowel is applied and the part where the mortar is sprayed can be bounded. There is a drawback that it is not possible to produce a good and high quality GRC panel.

  The present invention has been developed for the purpose of solving this drawback. An important object of the present invention is to prevent the aggregate from reflecting on the molding surface when spraying the mortar on the molding mold, and to form a three-dimensional plate-like shape with convex or concave portions on the surface and the inner surface. An object of the present invention is to provide a method of manufacturing a GRC panel that can efficiently mass-produce the GRC panel.

The manufacturing method of the GRC panel which makes the surface of the present invention three-dimensional shape sprays the mortar which mixed the aggregate and water into the cement with the air pressurized with the glass fiber on the inner surface of the mold, A GRC panel having a three-dimensional plate shape in which convex portions or concave portions are formed on the surface and the inner surface is manufactured. Furthermore, the method of the present invention makes the aggregate added to the mortar specific, limits the amount of aggregate added to a specific range, and also specifies the air pressure at which the mortar is injected into the mold. It is characterized by specifying the range. That is, as a mortar aggregate, a lightweight aggregate having a liter weight of 0.03 to 0.6 kg and a particle size of 3 mm or less is used. Furthermore, the addition amount of this lightweight aggregate shall be 8-15 weight% with respect to cement. Moreover, the air pressure which sprays this mortar on a forming mold shall be 1-3 kgf / cm < ² >.

  More preferably, the aggregate added to the mortar is a lightweight aggregate having a weight of 1 liter of 0.5 kg or less. As this lightweight aggregate, shirasu balloon or perlite of nacre and obsidian. Furthermore, the present invention manufactures a GRC panel that is suitable for an outer wall of a building, and is a three-dimensional plate-like GRC panel that has convex portions or concave portions on the surface and the inner surface.

The production method of the present invention has an advantage that when the mortar is sprayed on the molding frame, the aggregate is reliably prevented from being reflected from the molding surface, and a three-dimensional GRC panel can be efficiently mass-produced. This is because a lightweight aggregate having a specific gravity and particle size is used as the aggregate contained in the mortar to be sprayed on the forming mold, and the added amount of the lightweight aggregate is within a specific range. In the method of the present invention, a lightweight aggregate having a liter weight of 0.03 to 0.6 kg and a particle size of 3 mm or less is used as the aggregate of the mortar. Since this lightweight aggregate is small and light, its kinetic energy is small when it is sprayed and reflected on the molding surface of the molding frame and does not jump out of the mortar. The kinetic energy at which the lightweight aggregate is sprayed onto the molding surface of the molding frame is expressed by the following equation.
E = 1/2 × mv ²
In this equation, m is the mass of the aggregate, and v is the speed at which the aggregate collides with the molding surface.

As is apparent from this equation, the kinetic energy at which the aggregate collides with the molding surface increases in proportion to the product of the square of the velocity of the aggregate and the mass. When this kinetic energy increases, the force reflected from the molding surface of the molding frame and jumping out of the mortar increases. The mortar is viscous and tries to prevent the aggregate from popping out. However, in the conventional method, the kinetic energy that the aggregate tries to jump out of the mortar is larger than the force of the mortar preventing the jump out of the aggregate, and the jump out of the aggregate cannot be prevented. However, since the method of the present invention uses a small and light aggregate, the mass of one aggregate is extremely small. Since the kinetic energy at which the aggregate is about to jump out of the mortar is proportional to the mass, the kinetic energy at which the aggregate is about to jump out decreases as the mass decreases. Further, the production method of the present invention is directed to a pneumatic blowing mortar molding frame low as 1~3kgf / cm ^2. For this reason, the speed at which the mortar is sprayed onto the molding surface of the mold is also reduced, and this also reduces the kinetic energy at which the aggregate tends to fly out of the mortar. Synergistically, the production method of the present invention significantly reduces the kinetic energy when the aggregate collides with the molding surface on the molding frame. Furthermore, the production method of the present invention limits the amount of aggregate added to the mortar to 8 to 15% by weight. Therefore, even if the mortar is sprayed on the molding surface of the molding frame and the aggregate collides with the molding surface to repel it, a large amount of cement and water do not jump away from the viscous mortar. For this reason, the manufacturing method of the GRC panel of the present invention does not require the removal of the aggregate accumulated in the corners of the molding frame as in the prior art, and does not require special application of the mortar with a trowel. A simple method of spraying glass fiber onto a molding frame realizes the feature that a three-dimensional GRC panel having a protrusion on the surface can be efficiently mass-produced with high quality.

  Embodiments of the present invention will be described below with reference to the drawings. However, the examples shown below exemplify the manufacturing method of the GRC panel for embodying the technical idea of the present invention, and the present invention does not specify the manufacturing method of the GRC panel as follows.

  Mortar and glass fiber are sprayed from the nozzle 3 with pressurized air into the mold 1 having a cross-sectional shape shown in FIG. The molding frame 1 is formed by attaching a mortar and glass fiber to the inner surface to form a three-dimensional plate-shaped GRC panel 5 having convex portions or concave portions on the surface and the inner surface. The GRC panel 5 having a plate shape with a predetermined thickness as a whole has a concave portion on the inner surface when a convex portion is provided on the surface, and a convex portion on the inner surface when a concave portion is provided on the surface. As shown in the cross-sectional view of FIG. 3, the GRC panel 5 formed by the forming mold 1 of FIG. 2 is provided with convex portions 5A on both sides of the surface and a concave portion 5B in the middle. Therefore, the inner surface of the GRC panel 5 has the concave portions 5b on both sides and the convex portions 5a in the middle. The present invention relates to a method of manufacturing a three-dimensional plate-shaped GRC panel having convex portions or concave portions on the surface and the inner surface. The present invention is, for example, a surface of a surface molded with a molding mold shown in FIG. Various shapes of GRC panels can be manufactured, from a simple shape having convex portions on both sides and no concave portions on the inner surface to a complicated shape having a plurality of convex portions and concave portions on the surface.

  The inner surface of the mold 1 is the molding surface 2 of the GRC panel 5. This is because the GRC panel 5 is formed by attaching mortar and glass fiber to the inner surface to a predetermined thickness. Mortar and glass fiber are sprayed on the inner surface of the mold 1 to a predetermined thickness, and are formed into an uneven plate shape.

  Mortar is a mixture of aggregate and water in cement. Furthermore, in addition to these, a mortar can add a water reducing agent, a shrinkage reducing agent, and a thickener. The mortar is jetted from the nozzle immediately after kneading while kneading these raw materials. The glass fiber is cut into a predetermined length and sprayed from the nozzle together with the mortar. Glass fiber is sprayed from the center of the nozzle, and mortar is sprayed from around the glass fiber. A system in which mortar is continuously sprayed from a nozzle while kneading mortar, glass fiber is cut into a predetermined length, and mortar and glass fiber are sprayed together is called a direct spray system. In this method, the mortar and glass fiber sprayed from the nozzle are sprayed together on the molding surface of the molding frame, and the glass fiber is embedded in the mortar. However, the glass fiber can be cut into a predetermined length, kneaded into mortar, and sprayed from the nozzle.

  The mortar is sprayed from the nozzle 3 to the molding surface 2 of the molding frame 1 with pressurized air. Glass fiber is sprayed together with mortar from the nozzle 3 onto the molding surface 2 of the molding frame 1 with pressurized air. The glass fiber is cut into a predetermined length and sprayed from the nozzle 3 onto the molding surface 2, and the length of the glass fiber is about 30 mm. However, the length of the glass fiber can be 15 to 40 mm. The addition amount of glass fiber shall be 3-10 weight% with respect to mortar.

A mortar mixes a specific amount of unique aggregate. The aggregate mixed in the mortar is a lightweight aggregate having a weight of 1 liter of 0.03 to 0.6 kg. Further, this lightweight aggregate has a particle size of 3 mm or less. Furthermore, the addition amount of the lightweight aggregate is specified in the range of 8 to 15% by weight with respect to the cement. This mortar is sprayed from the nozzle 3 to the forming mold 1 with an air pressure of 1 to 3 kgf / cm ² .

If the weight of one liter of light aggregate is heavier than 0.6 kg and the particle size is larger than 3 mm, the mass of one aggregate will increase, and if this is sprayed on the molding surface 2 at a predetermined speed, it will move The energy increases and the light is reflected from the inner surface of the molding surface 2 of the molding die 1. Moreover, even if the addition amount of lightweight aggregate is more than 15% by weight, the probability of reflection from the molding surface 2 of the molding frame 1 to be sprayed increases. Further, even if the air pressure for injecting mortar onto the molding surface 2 of the molding die 1 is higher than 3 kgf / cm ² , the aggregate is reflected from the molding surface 2 of the molding die 1. This is because when the air pressure is high, the speed at which the mortar flies to the molding surface 2 increases, and the kinetic energy increases in proportion to the square of the speed.

When the weight of 1 liter of aggregate becomes lighter than 0.03 kg, the strength of the GRC panel 5 decreases. Even if the amount of aggregate added is less than 8% by weight, the strength of the GRC panel 5 is lowered or cracks are likely to occur. Furthermore, when the air pressure for injecting the mortar onto the molding surface 2 of the molding frame 1 is lower than 1 kgf / cm ² , the speed at which the mortar flies to the molding surface 2 is slowed down, and the mortar is molded efficiently and cleanly. 1 cannot be sprayed on the molding surface 2.

  A preferred lightweight aggregate to be added to the mortar is a shirasu balloon having a liter weight of 0.05 to 0.6 kg, preferably 0.05 to 0.5 kg, and a particle size of 1.0 mm or less. Furthermore, the lightweight aggregate to be added to the mortar is a pearlite system having a liter weight of 0.05 to 0.3 kg, preferably 0.05 to 0.2 kg, and a particle size of 1.2 mm or less. Perlite can be used. Further, a pearlite pearlite having a particle size of 1.2 mm or less and a pearlite having a particle size of 0.6 mm or less can be mixed and used. Furthermore, obsidian perlite with a liter weight of 0.6 kg or less and a particle size of 3 mm or less can be used, and obsidian perlite and pearlite perlite can also be used in combination. it can. Furthermore, the light aggregate can be used by mixing shirasu balloon and pearlite.

  The mortar can be added with water reducing agents, shrinkage reducing agents, thickeners and the like that are already on the market. The water reducing agent improves workability by reducing the amount of water added, and the amount added is 0.1 to 3% by weight. The shrinkage-reducing agent reduces shrinkage when cured and reduces the deviation, and its addition amount is 0.5 to 5% by weight. The thickener increases the viscosity of the mortar and reduces the reflection of the lightweight aggregate from the molding surface of the molding frame, and the addition amount is 0.01 to 0.5% by weight.

Mortar kneaded at the following mixing ratio is sprayed from the nozzle 3 onto the molding surface 2 of the molding frame 1 with pressurized air.
However, a shirasu balloon with a weight of 0.4 kg and a particle size of 1.0 mm or less is used for the lightweight aggregate.
Cement …………………………… 25kg
Shirasu Balloon (Lightweight Aggregate) ... 3.0kg
Shrinkage reducing agent …………………… 300g
Water reducing agent ……………………………… 800g
(Kao Corporation Mighty 150V)
Water …………………………………… 11 liters

The above mortar is sprayed from the nozzle 3 onto the molding surface 2 of the molding frame 1 with an air pressure of ² kgf / cm ² . The forming mold 1 is for forming the outer wall of a building, and has the shape shown in the cross-sectional view of FIG. 2 and has a width (W) of 90 cm and a depth (D) of 10 cm. The nozzle 3 sprays mortar from the periphery and glass fibers from the center of the mortar. The glass fiber sprayed from the nozzle 3 is cut into a length of 30 mm. Further, the glass fiber amount is 7% by weight with respect to the mortar.

As described above, when mortar and glass fiber are sprayed on the molding surface 2 of the molding frame 1 in a thickness of 3 cm, the aggregate contained in the mortar is not reflected from the molding surface 2 and is reflected on the molding surface 2. It was attached neatly. Furthermore, when the bending strength of the GRC panel 5 manufactured using the mortar and glass fiber of this mixing ratio was measured, it was extremely excellent at 250 kg / cm ² . Further, the specific gravity of the molded GRC panel 5 was as light as 1.5.

Mortar kneaded at the following mixing ratio is sprayed from the nozzle 3 onto the molding surface 2 of the molding frame 1 with pressurized air.
However, a pearlite pearlite having a liter weight of 0.08 kg and a particle size of 1.2 mm or less is used for the lightweight aggregate.
Cement …………………………… 25kg
Perlite (lightweight aggregate) …… 2.5kg
Shrinkage reducing agent …………………… 300g
Water reducing agent ……………………………… 800g
(Kao Corporation Mighty 150V)
Water …………………………………… 11 liters

The above mortar is sprayed from the nozzle 3 onto the molding surface 2 of the molding frame 1 with an air pressure of ² kgf / cm ² . The forming mold 1 is for forming the outer wall of a building, and has the shape shown in the cross-sectional view of FIG. 2 and has a width (W) of 90 cm and a depth (D) of 10 cm. The nozzle 3 sprays mortar from the periphery and glass fibers from the center of the mortar. The glass fiber sprayed from the nozzle 3 is cut into a length of 30 mm. Further, the glass fiber amount is 7% by weight with respect to the mortar.

As described above, when mortar and glass fiber are sprayed on the molding surface 2 of the molding frame 1 in a thickness of 3 cm, the aggregate contained in the mortar is not reflected from the molding surface 2 and is reflected on the molding surface 2. It was attached neatly. Furthermore, when the bending strength of the GRC panel 5 manufactured using the mortar and glass fiber of this mixing ratio was measured, it was extremely excellent at 250 kg / cm ² . Further, the specific gravity of the molded GRC panel 5 was as light as 1.5.

  As the aggregate, a pearlite pearlite with a liter weight of 0.01 kg and a particle size of 0.6 mm or less, and a pearlite system with a liter weight of 0.08 kg and a particle size of 1.2 mm Mortar and glass fiber were sprayed onto the molding surface 2 of the mold 1 in the same manner as in Example 2 except that pearlite was mixed so that the weight ratio was 50:50. Also according to this method, the aggregate contained in the mortar is not reflected from the molding surface 2 but is neatly attached to the molding surface 2, and a high-quality three-dimensional GRC panel 5 can be manufactured. Furthermore, the bending strength and specific gravity were comparable to Example 2.

Mortar and glass fiber were sprayed onto the molding surface 2 of the molding die 1 in the same manner as in Example 2 except that the air pressure at which the mortar was sprayed from the nozzle 3 was 3 kgf / cm ² . Also according to this method, the aggregate contained in the mortar is not reflected from the molding surface 2 but is neatly attached to the molding surface 2, and a high-quality three-dimensional GRC panel 5 can be manufactured. Further, the bending strength and specific gravity were the same as in Example 2.

  Mortar and glass fiber were sprayed onto the molding surface 2 of the molding frame 1 in the same manner as in Example 2 except that the addition amount of the lightweight aggregate was changed from 2.5 kg to 3.5 kg. Also according to this method, the aggregate contained in the mortar is not reflected from the molding surface 2 but is neatly attached to the molding surface 2, and a high-quality three-dimensional GRC panel 5 can be manufactured. Further, the bending strength and specific gravity were the same values as in Example 2.

It is sectional drawing which shows the state which manufactures a GRC panel with the conventional manufacturing method. It is sectional drawing which shows the state which manufactures a GRC panel with the manufacturing method concerning one Example of this invention. It is sectional drawing of the GRC panel manufactured with the shaping | molding die shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Molding form 2 ... Molding surface 2A ... Rising part 2B ... Horizontal part
2C ... Corner 3 ... Nozzle 4 ... Aggregate 5 ... GRC Panel 5A ... Convex 5B ... Concave
5a ... convex part 5b ... concave part

Claims (4)

A mortar mixed with aggregate and water in cement is sprayed onto the inner surface of a molding frame to be molded into a three-dimensional shape with glass fiber and pressurized air. A method of manufacturing a three-dimensional plate-shaped GRC panel capable of
As the aggregate, a lightweight aggregate having a liter weight of 0.03 to 0.6 kg and a particle size of 3 mm or less is used, and the added amount of the lightweight aggregate is 8 to 15 with respect to the cement. A method for producing a three-dimensional shape GRC panel, characterized in that a mortar having a weight% is injected from a nozzle to a molding frame with an air pressure of 1 to ³ kgf / cm ² and cured.   The method for producing a three-dimensional GRC panel according to claim 1, wherein a lightweight aggregate having a weight of 1 liter of 0.3 kg or less is used as the aggregate added to the mortar.   The method for producing a three-dimensional GRC panel according to claim 1, wherein a shirasu balloon or pearlite is used as an aggregate to be added to the mortar. The method for producing a three-dimensional GRC panel according to claim 1, wherein the fiber-reinforced concrete panel is an outer wall of a building.

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