JPH08133810A - Ultra-lightweight grc member and composition therefor and production of the member using the composition - Google Patents

Abstract

PURPOSE: To obtain a ultra-lightweight GRC member having mechanical strength comparable to or higher than those of conventional concrete materials etc., and about half in weight compared to conventional GRC. CONSTITUTION: This ultra-llghtweight GRC member has a specific gravity of 1.0-1.2, flexural strength of 100-130kgf/cm<2> and compressive strength of 200-300 kgf/cm<2> , being obtained from 100 pts.wt. of cement, 20-100 pts.wt. of lightweight aggregates, 5-20 pts.wt. of a synthetic resin emulsion (solid concentration at 45wt.%), 1-6 pts.wt. of glass fiber, 0.1-2 pts.wt. of a high-performance water reducing agent, 0.1-1.0 pt.wt. of a defoaming agent, 0.1-0.3 pts.wt. of a water-soluble resin, and 30-60 pts.wt. of water. Specifically, this GRC member is obtained by the following process: cement is dry-mixed with lightweight aggregates in advance, the mixture is incorporated with a synthetic resin emulsion, high- performance water reducing agent, defoaming agent and water-soluble resin followed by water, and the resultant mixture is kneaded and then mixed with glass fibers and further kneaded, and the resultant mixture is cast into a shuttering followed by conducting a steam curing and then demolding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultra-lightweight GRC (glass fiber reinforced concrete) member, a composition thereof, and a manufacturing method using the same.

[0002]

2. Description of the Related Art Conventionally, GRC has generally been composed of cement, glass fiber, silica sand, high performance water reducing agent and the like.

[0003] GRC is often used as a thin material because of its high strength, and as a result, it is made lighter in weight than ordinary concrete products.

[0004]

In recent years, larger panels such as decorative panels and decorative molds have been required. GRC is solid, and since the specific gravity of the material itself is γ≈2.3, if the material becomes large in size, it will become a considerable weight, and it will be difficult for a small number of people to carry and install it, leading to cost increase.

Under these circumstances, a light-weight GRC using a foaming agent and a lightweight aggregate (perlite etc.) has been developed up to now, but its strength is not sufficient (see, for example, Japanese Patent Laid-Open Publication No. Sho. 54-110222, JP-A-55-3330, JP-A-55-130873).

[0006] Therefore, most of the usages have been to reduce the weight as a thin material (by reducing the thickness) by taking advantage of the high strength characteristics of GRC (however, the density is large).
Further, glass fiber has a property of being deteriorated by alkali in cement, which is a drawback peculiar to GRC. Therefore, alkali-resistant glass fibers, low-alkali cement, etc. have been developed (for example, JP-A-55-142607).
No.

[0007] However, although a considerable effect can be obtained by the combination of these, the cost is considerably increased. or,
From the viewpoint of temperature control such as steam curing, low alkali cement is
It has the drawback of being difficult to handle.

Therefore, if ordinary cement is used, this will have the drawback that even alkali-resistant glass fibers will be deteriorated. On the other hand, although there are various methods for manufacturing GRC, the direct spray method is the mainstream method.

This is because glass fibers have the property of being difficult to disperse in the cement matrix. or,
A method of pouring into a mold by the premix method has also been proposed, but it has a drawback that it has poor fluidity and the shape of a manufacturable product is limited.

Therefore, according to the method of pouring into the mold,
When trying to obtain a thin-walled product, it was difficult to uniformly fill the mold with the material. Therefore, it is difficult to manufacture a thin product or a product having a complicated mold shape.

Other manufacturing methods include extrusion and pressing, but there is a drawback that the shape of the product that can be manufactured is limited. The present invention has been made to solve such a conventional problem, and an object thereof is to have a strength equal to or higher than that of a conventional concrete material or the like and a weight of the conventional GR.
It is to provide an ultra-lightweight GRC member which is about half of C.

Another object of the present invention is an ultra-lightweight GR which can enhance the dispersibility of glass fibers in a cement matrix and the reinforcing effect and can impart durability.
It is to provide a C composition.

Another object of the present invention is to provide a method for manufacturing an ultralight GRC by premixing (casting).

[0014]

The invention according to claim 1 is
It is characterized by having a specific gravity of 1.0 to 1.2 and a bending strength of 100 to 130 Kgf / cm ² .

The invention according to claim 2 is characterized in that the specific gravity is 1.0 to 1.2, the bending strength is 100 to 130 Kgf / cm ² , and the compression strength is 200 to 300 Kgf / cm ² . The invention according to claim 3 is a cement, a lightweight aggregate, a synthetic resin emulsion,
It is characterized by comprising glass fiber, a high-performance water reducing agent, a defoaming agent, a water-soluble resin, and water.

The invention according to claim 4 relates to 100 parts by weight of cement, 20 to 100 parts by weight of lightweight aggregate, 5 to 20 parts by weight of a synthetic resin (solid content concentration 45%) emulsion, and 1 to 6 of glass fibers. Parts by weight, high-performance water reducing agent 0.1 to 2 parts by weight, antifoaming agent 0.1 to 1.0 parts by weight, water-soluble resin 0.1 to 0.3 parts by weight, water
It is characterized by comprising 30 to 60 parts by weight.

In the invention according to claim 5, after the cement and the lightweight aggregate are kneaded in advance, the synthetic resin emulsion, the high-performance water reducing agent, the defoaming agent and the water-soluble resin are added, and then water is added and mixed. After kneading, and further adding glass fiber and kneading,
It is characterized by being poured into a formwork.

In the invention according to claim 6, after the cement and the lightweight aggregate are preliminarily kneaded, the synthetic resin emulsion, the high-performance water reducing agent, the defoaming agent, and the water-soluble resin are added, and then water is added and mixed. It is characterized in that it is kneaded, further kneaded by adding glass fibers, poured into a mold, steam-cured, and then demolded.

The invention according to claim 7 uses the composition for super-lightweight GRC member according to claim 4 to manufacture an ultra-lightweight GRC member.
After kneading 0 to 100 parts by weight beforehand, synthetic resin (solid content concentration 45%) emulsion 5 to 20 parts by weight and high performance water reducing agent 0.1 to
2 parts by weight, antifoaming agent 0.1-1.0 parts by weight, water-soluble resin 0.1-0.3
And 30 to 60 parts by weight of water are added and kneaded, and further 1 to 6 parts by weight of glass fibers are added and kneaded, and then poured into a mold.

The invention according to claim 8 is to manufacture an ultralight GRC member using the composition for an ultralight GRC member according to claim 4, wherein 100 parts by weight of cement is added to the lightweight aggregate 2.
After kneading 0 to 100 parts by weight beforehand, synthetic resin (solid content concentration 45%) emulsion 5 to 20 parts by weight and high performance water reducing agent 0.1 to
2 parts by weight, antifoaming agent 0.1-1.0 parts by weight, water-soluble resin 0.1-0.3
Parts by weight, and then, 30 to 60 parts by weight of water is added and kneaded, and further 1 to 6 parts by weight of glass fibers are added and kneaded,
It is characterized by pouring in a mold, steam curing, and then removing the mold.

The invention according to claim 9 is characterized in that, in the method for producing an ultra-lightweight GRC member according to any one of claims 5 to 8, the flow value of the material poured into the mold is 180 mm or more. To do.

According to a tenth aspect of the invention, in the method for manufacturing an ultra-lightweight GRC member according to the sixth or eighth aspect, the material is poured while applying vibration to the mold.

[0023]

Now, to reduce the weight of the concrete material means that the properties are contrary to each other, that is, the strength becomes weak. Therefore, in order to solve this problem, it is possible to cover the property of weakening the strength with fiber reinforcement. This is a conventionally known lightweight GRC.

Here, in order to cast it in a mold to produce various shapes, it must have high fluidity. However, when the fluidity is high, there is a problem that the lightweight aggregate and the cement, the glass fiber, or the like have a large difference in specific gravity, and thus are easily separated.

Therefore, the present inventors have focused on increasing the viscosity (viscosity) in order to prevent the separation of these materials, and have completed the present invention by adding a synthetic resin emulsion and a water-soluble resin. It was

The individual materials such as the synthetic resin emulsion, the water-soluble resin, and the high-performance water reducing agent used in the present invention basically have no effect on the hydration of cement. When used in combination, depending on the combination,
May delay or interfere with hydration of cement.

Therefore, it is necessary to find the optimum combination and determine the formulation design. That is the requirement specified in the claims. In the present invention, cement refers to ordinary Portland cement, early-strength Portland cement, and other Portland cement.

The lightweight aggregate has, for example, a particle size of 5 to 200.
Inorganic microballoons with μm and specific gravity of 0.3-0.7, particle size
There are organic microballoons with a thickness of 10 to 100 μm and a specific gravity of 0.04 or less.

As the inorganic microballoons, there are ceramic balloons, mineral balloons containing silicon and aluminum as main components, and as classification expressions, aluminum silicate balloons, alumina silicate balloons, glass microballoons, shirasu balloons. Including what is said to be.

Examples of organic microballoons include vinylidene chloride and vinyl chloride. The inorganic microballoons and the organic microballoons are used to reduce the weight.

The content of the lightweight aggregate was 20 to 100 parts by weight based on 100 parts by weight of cement. If it is less than 20 parts by weight, the effect of weight reduction is not obtained, and the desired ultra-light GRC cannot be obtained. If it exceeds 100 parts by weight, the strength of the ultra-light GRC itself becomes brittle.

As the synthetic resin emulsion, there are an acrylic type, a vinyl acetate type, a synthetic rubber type, a vinylidene chloride type, a vinyl chloride type or a mixture thereof having a surfactant property. Examples thereof include ethylene-modified vinyl acetate copolymer, acrylic styrene copolymer, and styrene-butadiene-rubber.

The synthetic resin emulsion was used in an amount of 5 to 20 parts by weight based on 100 parts by weight of cement. Below 5 parts by weight,
When it exceeds 20 parts by weight, the desired ultra-light GRC cannot be obtained because the dispersibility in the cement matrix and the reinforcing effect cannot be fully exhibited due to the inability to exhibit the surfactant properties and insufficient viscosity. Viscosity becomes too large, workability deteriorates, and fire resistance decreases.

The glass fiber is not particularly limited as long as it can be used for lightweight GRC, but alkali resistant glass fiber is preferable. The glass fiber content was 1 to 6 parts by weight based on 100 parts by weight of cement.

If the amount is less than 1 part by weight, the reinforcing effect cannot be obtained, and the desired ultralight GRC cannot be obtained. If the amount exceeds 6 parts by weight, the workability is deteriorated. The high-performance water reducing agent is added together with the synthetic resin emulsion in order to impart high fluidity, and by the balance between the high-performance water reducing agent and the synthetic resin emulsion, the dispersibility of glass fiber in the cement matrix and the reinforcing effect. Can be increased. Examples of the high performance water reducing agent include polycarboxylic acid high performance water reducing agents and melamine high performance water reducing agents.

The blending amount of the high-performance water reducing agent was 0.1 to 2 parts by weight with respect to 100 parts by weight of cement. If it is less than 0.1 part by weight, the effect of increasing fluidity is not obtained, and the desired ultralight GRC cannot be obtained. If it exceeds 2 parts by weight, the effect does not increase despite the increase in the amount added.

Examples of the defoaming agents include mineral oil nonionic surfactants and alcohol type defoaming agents. The defoaming agent content is
The amount was 0.1 to 1.0 part by weight with respect to 100 parts by weight of cement. 0.1
If it is less than the weight part, there is no effect, and the target super lightweight GRC
However, even if the amount exceeds 1.0 part by weight, the effect does not increase even if the amount added is increased.

The water-soluble resin is added to suppress the material separation between the lightweight aggregate and cement or the like. Examples of the water-soluble resin include carboxymethyl cellulose and methyl cellulose.

The content of the water-soluble resin was 0.1 to 0.3 parts by weight based on 100 parts by weight of cement. If it is less than 0.1 parts by weight, the effect of suppressing the material separation between the lightweight aggregate and cement cannot be exerted, and the desired ultralight GRC cannot be obtained, and if it exceeds 0.3 parts by weight, the viscosity increases too much, On the contrary, the workability becomes poor and it becomes difficult to pour it into the formwork.

Here, the synthetic resin emulsion and the high-performance water-reducing agent have a high fluidity depending on the balance between them, and the dispersibility of the glass fiber in the cement matrix and the reinforcing effect can be enhanced.

Furthermore, the addition of the synthetic resin emulsion has the effect of suppressing the deterioration of the glass fiber cement by alkali. Next, a method for manufacturing the ultralight GRC of the present invention will be described.

FIG. 1 shows a process of a method for manufacturing an ultralight GRC of the present invention. First, in step S1, materials are mixed. Here, the mixing of materials is
There are cases where the cement and the lightweight aggregate are preliminarily kneaded, and cases where the necessary materials are mixed.

Next, in step S2, the synthetic resin emulsion, the high-performance water reducing agent, the defoaming agent, and the water-soluble resin are added, and then water is added and kneaded. Further, glass fibers are added and kneaded. To do.

By this step S2, the super lightweight GRC
The composition is complete. The softness of the material here is
In consideration of workability, the flow value specified in JIS R5201 (Cement physical property test method) shall be 180 mm or more.

Next, in step S3, the superlight GRC composition kneaded in step S2 is poured and compacted while shaking the mold. Next, in step S4,
A mold filled with an ultralight GRC composition is steam-cured.

Next, in step S5, the mold is removed. Thus, in step S6, an ultralight PC (precast concrete) member made of the ultralight GRC composition can be obtained.

The physical properties of the ultralight GRC member obtained here are as follows. Specific gravity 1.0-1.2 Bending strength 100-130Kgf / cm ² Compressive strength 200-300Kgf / cm ² Drying shrinkage 3-10 × 10 ^-4 Thermal conductivity λ = 0.1-0.3Kcal / mh ℃ Flow value 180mm or more Also, the present invention In this case, since lightweight aggregate is used instead of silica sand used in the conventional GRC, it becomes easy to cut with a saw or the like.

[0048]

The present invention will be described below with reference to examples. Example 1 (In-room mortar performance test) For 100 parts by weight of ordinary Portland cement, 40 parts by weight of a ceramic balloon (ultra-lightweight aggregate) was placed in a mortar mixer in advance and kneaded, and then an acrylic resin synthetic resin emulsion ( Solid content concentration 45%) 11.1 parts by weight, 1 part by weight of a melamine-based high-performance water reducing agent, 0.2 parts by weight of an alcohol-based antifoaming agent, and 44 parts by weight of water (water / cement = 50%) was added and mixed. .

Here, the specific gravity of kneading was 1.37 and the flow value was 183 mm. After observing the uniform kneading, add 5.9 parts by weight of glass fiber (Nippon Electric Glass Co., Ltd., alkali resistant glass fiber (single fiber Φ13.5 μm; 400 convergent type)) and knead. R52
An ultralight GRC molded body was prepared by packing it in a mold specified in 9.4 of 01 (Cement physical testing method).

This was packed in a mold and cured in a steam curing chamber at 60 ° C. for 6 hours, and then demolded. After demolding, the test body was allowed to stand in a standard curing room (temperature 20 ± 3 ° C., humidity 65 ± 5% RH) and the strength and air-dry specific gravity were measured for each age.

The results are shown in Table 1. Example 2 (Performance test of mortar in a room) For 100 parts by weight of ordinary Portland cement, 40 parts by weight of ceramic balloon (ultra-lightweight aggregate) was put in a mortar mixer in advance and kneaded, and then acrylic resin synthetic resin emulsion ( Solid content concentration 45%) 11.1 parts by weight, melamine-based high-performance water reducing agent 1 part by weight, alcohol-based antifoaming agent 0.2 parts by weight, and water 49 parts by weight (water / cement = 55%) was added and mixed. .

Here, the kneading specific gravity was 1.36 and the flow value was 217 mm. After observing that they were uniformly kneaded, 5.9 parts by weight of glass fiber (manufactured by Nippon Electric Glass Co., Ltd., alkali-resistant glass fiber (single fiber Φ13.5 μm; 400 convergent type)) was added and kneaded. R52
An ultralight GRC molded body was prepared by packing it in a mold specified in 9.4 of 01 (Cement physical testing method).

This was packed in a mold and cured in a steam curing chamber at 60 ° C. for 6 hours, and then demolded. After demolding, the test body was allowed to stand in a standard curing room (temperature 20 ± 3 ° C., humidity 65 ± 5% RH) and the strength and air-dry specific gravity were measured for each age.

The results are shown in Table 1. Example 3 (Performance test of mortar in room) 40 parts by weight of ceramic balloon (ultra-lightweight aggregate) was put into a mortar mixer in advance with respect to 100 parts by weight of ordinary Portland cement, and kneaded with acrylic resin synthetic resin emulsion ( Solid content concentration 45%) 11.1 parts by weight, melamine-based high-performance water reducing agent 1 part by weight, alcohol-based antifoaming agent 0.2 parts by weight, and water 54 parts by weight (water / cement = 60%) were added and mixed. .

Here, the kneading specific gravity was 1.34 and the flow value was 228 mm. After observing the uniform kneading, add 5.9 parts by weight of glass fiber (Nippon Electric Glass Co., Ltd., alkali resistant glass fiber (single fiber Φ13.5 μm; 400 convergent type)) and knead. R52
An ultralight GRC molded body was prepared by packing it in a mold specified in 9.4 of 01 (Cement physical testing method).

This was packed in a mold and cured in a steam curing chamber at 60 ° C. for 6 hours, and then demolded. After demolding, the test body was allowed to stand in a standard curing room (temperature 20 ± 3 ° C., humidity 65 ± 5% RH) and the strength and air-dry specific gravity were measured for each age.

The results are shown in Table 1.

[0058]

[Table 1]

Example 4 (Prototype Experiment of Ultra-lightweight GRC Material in Factory) 40 parts by weight of ceramic balloon (ultra-lightweight aggregate) was put into a large mortar mixer in advance and kneaded with 100 parts by weight of ordinary Portland cement. After that, 11.1 parts by weight of acrylic resin synthetic resin emulsion (solid content concentration 45%), 1 part by weight of melamine-based high-performance water reducing agent, 0.2 parts by weight of alcohol-based defoaming agent, 0.2 parts by weight of methyl cellulose (water-soluble resin), and water. 43.9 parts by weight were added and kneaded.

After observing that the mixture was uniformly kneaded, further glass fiber (manufactured by Nippon Electric Glass Co., Ltd., alkali resistant glass fiber (single fiber Φ13.5 μm; 400 convergent type)) 5.9
After adding parts by weight and kneading, pour it while vibrating it on a steel frame for production of glutes, plates, etc. prepared in advance,
An ultra-lightweight GRC molded product was created.

On the other hand, in a trial experiment at this factory, a part of the kneaded mortar was JIS R prepared in the same manner as in Example 1.
An ultralight GRC molded body was prepared by packing it in a steel form specified in 9.4 of 5201 (physical test method for cement).

This was packed in a mold and steam-cured in a steam-curing room at 60 ° C. for 6 hours, and then demolded. After demolding, the test body was allowed to stand in a standard curing room (temperature 20 ± 3 ° C., humidity 65 ± 5% RH) and the strength and air-dry specific gravity were measured for each age.

The results are shown in Table 2.

[0064]

[Table 2]

[0065]

As described above, according to the invention described in claims 1 to 10, the weight is about half (γ = 1.0 to 1.2) as compared with the conventional GRC, and the strength is equal to the conventional concrete strength. Bending strength above: 100-130Kgf / cm ² , compressive strength: 2
It is possible to obtain 00 to 300 Kgf / cm ² . Therefore, the conventional G
It is possible to further reduce the weight by replacing the RC.

Therefore, not only can the structure be made lightweight, but the workability can be improved and the cost can be reduced. Since it can be manufactured by pouring, it is possible to manufacture ultra-light GRCs of various shapes that are rich in variety of products.

By virtue of the balance of the synthetic resin emulsion, the high-performance water reducing material, the water-soluble resin and the defoaming agent, it is possible to prevent the separation due to the difference in specific gravity between the aggregate and the cement while having a high fluidity.

Further, the finished product is clean. By using a vibrator together with pouring and steam curing,
Since the manufacturing speed can be increased, the super lightweight GRC can be manufactured in the process of 2 revolutions / day.

Since the ultra-lightweight GRC uses lightweight aggregate, it can be easily cut by a saw or the like.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a manufacturing process of the present invention.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication C04B 24:12 A 24:02 24:38 D 14:42) A 103: 30 103: 40 103: 50 111: 40

Claims (10)

[Claims] 1. Specific gravity 1.0 to 1.2, bending strength 100 to 130 Kgf / cm
Ultra lightweight GRC member characterized by being ² . 2. Specific gravity 1.0 to 1.2, bending strength 100 to 130 Kgf / cm
^2. An ultra-lightweight GRC member having a compressive strength of 200 to 300 Kgf / cm ² . 3. Cement, lightweight aggregate, synthetic resin emulsion, glass fiber, high-performance water reducing agent, and defoaming agent,
Super lightweight G characterized by consisting of water-soluble resin and water
Composition for RC member. 4. Light-weight aggregate 20 per 100 parts by weight of cement
~ 100 parts by weight, synthetic resin (solid content concentration 45%) emulsion 5 to 20 parts by weight, glass fiber 1 to 6 parts by weight, high performance water reducing agent 0.1 to 2 parts by weight, defoaming agent 0.1 to 1.0 parts by weight Parts, 0.1 to 0.3 parts by weight of a water-soluble resin, and 30 to 60 parts by weight of water. 5. A cement and a lightweight aggregate are preliminarily kneaded, then a synthetic resin emulsion, a high-performance water reducing agent, a defoaming agent, and a water-soluble resin are added, and then water is added and kneaded. A method for producing an ultra-lightweight GRC member, which comprises adding and kneading, and then pouring into a mold. 6. A cement and a lightweight aggregate are preliminarily kneaded, and then a synthetic resin emulsion, a high-performance water reducing agent, a defoaming agent and a water-soluble resin are added, and then water is added and kneaded. A method for manufacturing an ultra-lightweight GRC member, which comprises: kneading and kneading, pouring into a mold, steam curing, and then demolding. 7. When manufacturing an ultralight GRC member using the composition for an ultralight GRC member according to claim 4, after 100 parts by weight of cement, 20 to 100 parts by weight of lightweight aggregate is preliminarily kneaded. , Synthetic resin (solid content 45%) emulsion 5 to 20 parts by weight, high-performance water reducing agent 0.1 to 2 parts by weight, and defoaming agent 0.1
To 1.0 part by weight and 0.1 to 0.3 parts by weight of a water-soluble resin, and then 30 to 60 parts by weight of water and kneading, and further 1 to 6 parts by weight of glass fiber and kneading, and then a mold. A method for manufacturing an ultra-lightweight GRC member, which is characterized in that 8. When manufacturing an ultralight GRC member using the composition for an ultralight GRC member according to claim 4, after kneading 20 to 100 parts by weight of lightweight aggregate with respect to 100 parts by weight of cement in advance. , Synthetic resin (solid content 45%) emulsion 5 to 20 parts by weight, high-performance water reducing agent 0.1 to 2 parts by weight, and defoaming agent 0.1
To 1.0 part by weight and water-soluble resin 0.1 to 0.3 parts by weight, and then 30 to 60 parts by weight of water and kneading, and further 1 to 6 parts by weight of glass fiber and kneading to form a mold. Super lightweight GRC characterized by pouring and steam curing followed by demolding
A method of manufacturing a member. 9. The method for manufacturing an ultra-lightweight GRC member according to claim 5, wherein the flow value of the material poured into the mold is 180 mm or more. Production method. 10. The ultralight G according to claim 6 or claim 8.
A method for manufacturing an ultra-lightweight GRC member, which comprises pouring a material while applying vibration to a mold in the method for manufacturing an RC member.