JPH08268775A - Lightweight concrete block and its production - Google Patents

Abstract

PURPOSE: To obtain a lightweight concrete block light in weight, having durability and capable of producing simply and to provide its producing method. CONSTITUTION: This lightweight concrete block, having a specific gravity of about 1.4-2.0, is produced by kneading a synthetic resin foamed product, water, a hydraulic bonding material and a fine aggregate such as sand, and press- molding the kneaded mixture before hardening of the hydraulic bonding material. The press molding process is preferably performed under about >=50kgf/cm<2> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightweight concrete block obtained by pressure molding a lightweight concrete containing a synthetic resin foam, and a method for producing the same.

[0002]

2. Description of the Related Art As another technique similar to this type of manufacturing method, there is a method for manufacturing a building material in Japanese Patent Publication No. 3-69868, which is a foamed plastic having a hard film for pressure resistance on its surface. The particles are mixed with a hydraulic inorganic material, and the inorganic material is pressure-molded in the presence of water. or,
Conventionally, for the purpose of weight reduction, a cement molded product obtained by mixing pearlite, shirasu balloon or the like into cement and molding the mixture into a predetermined shape by press molding is also used.

[0003]

According to the method for manufacturing a building material, it is difficult to make a uniform thickness when a hard film is attached to the surface of expanded plastic particles, and as a result,
There is a problem that it is difficult to obtain a uniform product due to a difference in strength inside the product. Further, although a hard film is formed on the surface of the expanded plastic particles, its thickness is thin and non-uniform, so that the expanded plastic particles contract to some extent due to the external pressure at the time of pressure molding, and as a result, There is a problem that after expansion due to pressure release, swelling occurs and unevenness is formed on the surface of the building material, resulting in inferior product value. Further, there is a problem that it is extremely difficult to form a hard film on the surface of each small particle having a diameter of about 0.1 to 15 mm.

On the other hand, the conventional cement molded product containing pearlite or shirasu balloon is difficult to obtain a predetermined product size because the mixed pearlite is easily crushed during kneading or press molding. There is. Further, since water-permeable bubbles are present, there is a problem that watertightness and freeze-thaw resistance are poor, and it is difficult to obtain sufficient durability.

[0005]

SUMMARY OF THE INVENTION The present invention is intended to solve such problems and provide a practical lightweight concrete block and a method for producing the same. Therefore, the lightweight concrete block according to claim 1 is made by kneading a synthetic resin foam, water, a hydraulic binder, and fine aggregate such as sand, and press-molding before hardening the hydraulic binder to obtain a specific gravity. It is characterized in that it is a lightweight concrete block of approximately 1.4 to 2.0. As fine aggregates such as sand, fine aggregates such as blast furnace slag fine aggregates and structural lightweight concrete aggregates can be used in addition to sand.

The lightweight concrete block of claim 2 is
In the structure of claim 1, the synthetic resin foam is a bead having an average particle diameter of about 2 mm or less.

The lightweight concrete block according to claim 3 is
In the structure of claim 1 or 2, polystyrene (EPS: expanded polystyrene) is used as the synthetic resin foam.

The lightweight concrete block according to claim 4 is
In the structure according to any one of claims 1 to 3, the specific gravity of the synthetic resin foam is approximately 0.05 to 0.20.

The lightweight concrete block according to claim 5 is
The structure according to any one of claims 1 to 4, wherein the obtained lightweight concrete block contains a synthetic resin foam in a volume of approximately 10 to 40%.

The lightweight concrete block of claim 6 is
In the structure according to any one of claims 1 to 5, fine aggregate such as sand having a volume of about 10 to 40% in the obtained lightweight concrete block (hereinafter, may be simply referred to as sand).
It is characterized by containing.

The lightweight concrete block according to claim 7 is
The structure according to any one of claims 1 to 6, wherein the fiber reinforcement is mixed in an absolute volume of approximately 0.1 to 0.6%.

The lightweight concrete block according to claim 8 is
The structure according to any one of claims 1 to 7, wherein the hydraulic binder is cement.

The lightweight concrete block according to claim 9 is
The structure of claim 8 is characterized in that fly ash and / or blast furnace slag is mixed in approximately 10 to 35% by weight of the cement weight.

According to the tenth aspect of the lightweight concrete block of
The manufacturing method is the lightweight concrete according to any one of claims 1 to 9.
The pressure molding of the heat block produces a pressing force of approximately 50 kg.
f / cm ²It is characterized by the press forming process described above
Things.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION First, a lightweight concrete block according to claim 1 will be described. As the raw material of the synthetic resin foam used here, various known ones can be used and are not particularly limited, and the outer shape thereof is, for example,
It may be a crushed product obtained by crushing a synthetic resin foam molded product or an irregular shape, but the one formed into spherical or substantially spherical beads has less weighing error and less variation in specific gravity,
Since the stress is easily dispersed, it is easy to obtain a strong product,
It is suitable.

Examples of the synthetic resin used as the raw material of the synthetic resin foam include styrene resins such as polystyrene, olefin resins such as polypropylene and polyethylene,
Various copolymers such as acrylonitrile-styrene copolymer, styrene-ethylene copolymer (including, of course, random, block, graft, etc.), polyvinyl chloride, polyvinyl chloride resin such as polyvinylidene chloride, etc. Of these, the use of polystyrene is the most desirable because of its high strength and low cost.

Using such a synthetic resin foam as an aggregate, it is mixed with a mixture of at least a hydraulic binder, water, sand and the like and kneaded, and this hydraulic binder composition is pressure-molded. A lightweight concrete block having a specific gravity of approximately 1.4 to 2.0 is obtained. If the specific gravity of the block is less than 1.4, it will be extremely preferable from the viewpoints of weight reduction and heat insulation, but since the mixing ratio of the synthetic resin foam increases, the strength of the block tends to decrease, and The price tends to be expensive. On the contrary, if the specific gravity exceeds 2.0, there is a tendency that the specific gravity is not so preferable from the viewpoints of weight reduction, cuttability and heat insulation.

As the hydraulic binder, cement, lime,
Examples of the cement include gypsum and adhesives. Among them, cement is the most desirable because it has high strength, excellent water resistance, and is relatively inexpensive. As the cement, ordinary Portland cement, early strength Portland cement, super early strength Portland cement, Portland cement such as moderate heat Portland cement, or blast furnace cement, silica cement,
Mixed cement such as fly ash cement, or
Ultra early strength cement, expansive cement, special cement such as cosmetic cement (white cement, color cement, etc.), or alumina cement can be used, and it is preferable to use properly depending on the application.

Sand and the like are mixed in the hydraulic binder composition at the time of molding for the purpose of improving the shape retention function. That is, the sand or the like plays a role of reducing the amount of deformation that occurs when the synthetic resin foam is compressed inside the hydraulic binder composition during pressure molding, in addition to the normal action as a fine aggregate. The synthetic resin foam is pressed during pressure molding,
If it deforms more than a certain amount, it will buckle easily and will recover after releasing pressure, so small irregularities or microcracks will easily form on the surface of the product, but the pressure applied from the outside will be absorbed by the inclusion of sand etc. As a result of reducing the deformation and buckling of the synthetic resin foam, there is an advantage that a change in shape after pressure release is prevented and a smooth surface is obtained. The particle size of the sand may be in the range of usually 5 mm or less, and the type thereof is not particularly limited.

A synthetic resin foam, a hydraulic binder, a hydraulic binder composition containing water, sand and the like are dehydrated and molded into a predetermined block shape and cured to have a specific gravity of about 100%. A lightweight concrete block of 1.4 to 2.0 was obtained. The water binder ratio (W / C) of the hydraulic binder composition is preferably about 40% or less.
It is preferably around 25%. The amount of hydraulic binder such as cement is 20% by volume in the hydraulic binder composition.
It is preferable that the amount used is from 35 to 35% by volume, preferably from 22 to 32% by volume, more preferably from 25 to 30% by volume.

The specific gravity of the hydraulic binder composition and the specific gravity of the lightweight concrete block obtained by dehydration molding this composition into a predetermined block shape by pressure molding such as press molding and then curing the composition are almost the same. Although the same, the reason is that the hydraulic binder composition (for example, water binder ratio (W /
The water in (C) is 40%) is partially removed by dehydration molding (the above (W / C) is reduced to about 25%, for example). The specific gravity of the block is higher than that of the composition by, for example, about 0.1 because it is larger than that of the composition. However, by curing and drying the block after dehydration molding, the weight of water is about 5 to 6% by weight. Is released (during which the volume of the block hardly changes), and as a result, the specific gravity of the block decreases by about 0.1 during curing and drying. Therefore, the specific gravity of the hydraulic binder composition and the specific gravity of the resulting block are reduced. And are almost equal.

As described above, a lightweight concrete block is obtained by molding the hydraulic binder composition in a state where the hydraulic binder is uncured. In this case, the molding process is usually performed by pressing. The molding may be, for example, press molding or extrusion molding using an extruder. Which is adopted is appropriately selected mainly depending on the shape of the desired product. After molding, for example, it is used as a product after being cured in air, in water, steam, or in an autoclave for a predetermined time.

The lightweight concrete block of the present invention produced as described above is a paving block, an outer wall, a partitioning material, a floorboard, a floor, a fence, a waterproof layer for a rooftop, a terrace or a balcony or a pressing material for a heat insulating material, It can be used for various purposes such as drainage gutters, gutter lids, OA floors, and partition materials for flower beds. Furthermore, the lightweight concrete block of the present invention can be applied to various containers such as ornaments and flowerpots in addition to the above-mentioned use as a normal block. In the present specification, such ornaments and containers are used for convenience. Is also called a block.

The lightweight concrete block according to claim 2 is
As described above, by making the synthetic resin foam into a spherical or substantially spherical bead-shaped particle shape, variations in measurement error and specific gravity are reduced, and stress is easily dispersed.
In addition to the advantage that a strong product can be obtained, the average particle size is about 2 mm or less, more preferably about 1.5 mm or less, and most preferably about 1 mm or less.

The reason for this is that the buoyancy of the synthetic resin foam is reduced by making the average particle size of the particles smaller than approximately 2 mm, and the floating of the synthetic resin foam can be effectively prevented. A hydraulic binder that makes the body even,
It is easy to disperse in a mixture of water and sand, it is easy to obtain a product having an average density, and the fluidity of a mixture of hydraulic binder, water, sand and synthetic resin foam is good. The average particle size of the synthetic resin foam is 0.1 to 1
mm is preferable from the viewpoint of fluidity and dispersibility.

On the other hand, if the average particle size of the synthetic resin foam is less than 0.1 mm, it will be too small, and the fluidity of the kneaded product will tend to decrease when kneading with water and the hydraulic binder. Since it is difficult to secure a sufficient amount of the synthetic resin foam mixed, it tends to be difficult to reduce the weight.
If the average diameter exceeds 2 mm, the buoyancy of the synthetic resin foam increases and tends to separate from the hydraulic binder.
It is not preferable because it is difficult to obtain a uniform product and the strength tends to be weakened. The average diameter when the synthetic resin foam is a crushed product or has a different shape is expressed as an average value of the maximum length and the minimum length.

The lightweight concrete block according to claim 3 is:
By using polystyrene as a raw material of the synthetic resin foam, it is most desirable because it has high strength and is inexpensive.

The lightweight concrete block according to claim 4 is
The specific gravity of the synthetic resin foam is set in the range of 0.05 to 0.20, because it is easy to obtain appropriate strength and is economically preferable. When this is converted into a foaming ratio, it is within a range of approximately 5 to 20 times. When the specific gravity of the synthetic resin foam is less than 0.05,
The strength of the completed block tends to be weak,
On the other hand, if the specific gravity exceeds 0.20, the material cost will be high although it is excellent from the viewpoint of strength.

A fifth aspect of the present invention is that the content of the synthetic resin foam in the obtained lightweight concrete block is in the range of approximately 10 to 40% by volume. If it is less than 10%, the weight reduction and the cutting property and the heat insulating property tend to be insufficient, which is not preferable. On the other hand, if it exceeds 40%, it is extremely preferable from the viewpoints of weight reduction and heat insulation, but the content ratio of the synthetic resin foam becomes excessively large, so that the strength of the block tends to decrease, and also in terms of price. It tends to be expensive.

According to a sixth aspect, the content of fine aggregate such as sand in the obtained lightweight concrete block is approximately 1 in absolute volume.
The range is 0 to 40%, more preferably 20 to 35%, and most preferably 27 to 31%. The reason is that when the content of sand or the like is less than 10%, the aggregate of the synthetic resin foam is likely to buckle during the molding process, and the restoring force of the buckled synthetic resin foam causes the surface of the block or the inside of the block to be restored. Microcracks easily occur on the
Bending strength and surface properties tend to deteriorate. on the other hand,
When the content of sand or the like exceeds 40%, it is not so preferable from the viewpoints of weight reduction, cutting property and heat insulating property. When sand is used as the fine aggregate, this sand may have a particle size of 5 mm or less, which is usually used as a fine aggregate for concrete, and a specific gravity in the range of, for example, about 2.6. It is not limited. Also, instead of sand, blast furnace slag fine aggregate (grain size 5 mm or less, specific gravity, for example, about 2.0 to 2.6) or JIS A 5002, as specified in JIS A 5012 A fine aggregate of structural lightweight concrete aggregate (having a grain size of 5 mm or less and a specific gravity of, for example, about 1.3 to 2.3) can be used.

Further, in the lightweight concrete block of the present invention, a preferable result can be obtained when the total amount of the sand or the like and the amount of the synthetic resin foam mixed is 40 to 50% in absolute volume. The reason is that if it is less than 40%, the amount of dehydration tends to increase at the time of pressure molding and the thickness of the product may become thin. On the other hand, if it exceeds 50%, the fluidity tends to deteriorate. This is because the pressure molding time may be long and the filling property may be deteriorated.

The lightweight concrete block according to claim 7 is:
A fiber reinforcing material, preferably an alkali resistant glass fiber is mixed in an absolute volume of 0.1 to 0.6%, which makes it possible to obtain a lightweight concrete block which is tough and has a high bending strength. Examples of the fiber reinforcing material include alkali glass fiber, vinylon fiber, nylon fiber, polypropylene fiber and the like. Of these, alkali-resistant glass fibers have high flexural strength and are resistant to the alkalinity of cement, and therefore are particularly preferably used when the hydraulic binder is cement.

The length of the alkali resistant glass fibers is preferably about 10 mm to 20 mm on average, but is not particularly limited to this range. If the mixing ratio of the fiber reinforcing material such as alkali-resistant glass fiber is less than 0.1% in absolute volume, the bending strength tends to be weak, and if it exceeds 0.6%, the fluidity of the mortar tends to decrease. Therefore, the pressure molding time tends to be long, the filling property tends to be poor, and the manufacturing cost tends to be high. Therefore, the above range is appropriate.

The lightweight concrete block according to claim 8 is
By using cement as the hydraulic binder, as described above, advantages such as high strength, excellent water resistance, and relatively low price can be obtained.

In a ninth aspect, as a further alkali resistance measure when cement is used as the hydraulic binder, the alkalinity of the cement is lowered by mixing fly ash and / or blast furnace slag, etc. It is a weak alkali. Further, when fly ash or the like is mixed in the cement, the fluidity is improved, the surface is made beautiful, and the synthetic resin foam is less likely to appear on the surface of the block. Further, the long-term strength is improved and a block having high strength is obtained.

The mixing ratio of fly ash and / or blast furnace slag is preferably about 10 to 35%, more preferably 15 to 35%, and further preferably 20 to 27% based on the weight of cement.
Is most preferred. If the mixing ratio exceeds 35% by weight, the initial strength tends to decrease, which is not preferable. If the mixing ratio is less than 10% by weight, the effect of mixing tends to be poor. These fly ash have a specific surface area of about 2400 cm ² / g or more, and the blast furnace slag has a specific surface area of about 30.
A powdery material having a size of 00 cm ² / g or more is used.

When the synthetic resin foam, water, hydraulic binder and sand are mixed, various admixtures such as AE agent,
By mixing a water reducing agent, an AE water reducing agent, a high-performance AE water reducing agent, etc., the strength of the obtained block can be improved by, for example, about 10%. Also, when it is preferable to color the block depending on the use of the block, a colorant is mixed within about 5% of the cement weight when mixing the synthetic resin foam, water, hydraulic binder and sand. According to this method, for the obtained block,
There is an advantage that the trouble of coloring again by painting etc. can be saved.

The lightweight concrete block of claim 10
The manufacturing method is the lightweight concrete according to any one of claims 1 to 9.
The pressure molding of the heat block produces a pressing force of approximately 50 kg.
f / cm ²It is characterized by the press forming process described above
It Pressing force is 50 Kgf / cm²When the pressure is less than
It tends to take a long time, and it is useful for smooth molding.
This is because there may be problems. In addition, the above pressure molding
Extrusion molding is performed by press molding.
Complex shapes not possible with other pressure forming processes such as machining
The block is also designed to be easily manufactured.

For example, in the usual molding of thick slate, the pressing pressure is about 120 to 150 Kgf / cm ² , and the strength lowers when the molding pressure is 120 Kgf / cm ² or less. On the other hand, in the molding of the present invention, approximately 50 Kgf / c
Since it can be molded in a range of m ² or more, preferably about 50 to 150 Kgf / cm ² , and more preferably about 70 to 100 Kgf / cm ² , it can be molded even by a press machine having a small press capacity, which is industrially preferable.

[0040]

Embodiments of the present invention will be described below. First,
Tables 1 and 2 show blending examples of lightweight concrete in Examples and Comparative Examples of the present invention. Here, EPS represents expanded polystyrene. Further, the beads represent spherical or substantially spherical particles, but the EPS beads may be simply referred to as EPS.

[Table 1] The values in parentheses in Tables 1 and 2 show the volume ratio when the entire hydraulic binder composition is 1.

[0041]

[Table 2]

In the above formulation examples, the synthetic resin foam is made of polystyrene foam having a specific gravity of 0.05 or 0.1.
Beads having an average diameter of 0 and 0.20 and a diameter of 0.9 mm were used. As the cement, ordinary Portland cement was used. Further, as the fiber reinforcing material, 13 mm of alkali resistant glass fiber was used. For sand, the diameter is 2.5 mm
The following river sand was used. Using the lightweight concrete of each example and each comparative example mixed as described above, a thickness of 4 cm,
A test body having a width of 40 cm and a length of 40 cm was prepared. Press molding is performed by pouring a predetermined amount of the lightweight concrete into the lower mold and pressurizing it from above with a press at a pressure of 70 kg / cm ² through the upper mold, and then curing and hardening at room temperature for about 24 hours, The formwork was removed and underwater curing was performed. Then, various performance tests were conducted, and the results shown in Tables 3 and 4 were obtained.

[0043]

[Table 3]

[0044]

[Table 4]

As is clear from Tables 3 and 4, the lightweight concrete blocks of the examples of the present invention have a smaller density than the conventional concrete blocks shown as comparative examples. Although the compressive strength and bending strength are slightly low, they are strengths that pose no practical problems. In Example 4, the surface property is improved by mixing the fly ash, and in Example 5, the bending strength is maximized by mixing the alkali resistant glass fiber. On the other hand, in Comparative Example 4, since the synthetic resin foam has a small specific gravity, cracks are generated on the surface of the block and the bending strength is low.

Further, in Comparative Example 3 in which the proportion of sand was small, unevenness was formed on the surface of the plate-like body. On the other hand, Comparative Example 6 with a large proportion of sand
It can be seen that is naturally heavy and has a high surface dry density. Further, Comparative Example 6 had a problem that cutting was difficult. The cuttability is determined by whether or not it can be cut by an electric saw. On the other hand, in Examples 1 to 6 included in the manufacturing method of the present invention, it was possible to obtain a clean product having a flat surface. Further, since it contains a large amount of synthetic resin foam beads, it is possible to obtain a product excellent in watertightness in addition to being able to reduce the weight and having a high compressive strength and a low water absorption rate. It was Although the non-flammability of Example 1 is unacceptable, the lightweight concrete block has various uses, and a high non-flammability is required depending on the use and a relatively low non-flammability is sufficient. (For example, a drain, etc., which is constantly in contact with water). In the latter case, the block of Example 1 can also be preferably used. In addition, although the thickness of Example 1 may be slightly thin, this point is not a problem depending on the application.

In addition to the above-mentioned Examples and Comparative Examples, the average particle size of EPS beads was 1.2 m in the formulation of Example 4.
m, 1.7 mm, and 2 mm were exceeded, but an experiment was performed only by changing to three types. As a result, the one having a thickness of 1.2 mm has a good surface property, and there are few surface irregularities. In addition, although the product having a diameter of 1.7 mm was able to be mixed with the hydraulic binder composition and a product was obtained, some surface irregularities were observed. If it exceeds 2 mm, the composition tends to separate, and mixing tends to be difficult, so that a product is difficult to manufacture.

[0048]

As is apparent from the above description, according to the lightweight concrete block of the present invention, the synthetic resin foam, water, the hydraulic binder and the sand are kneaded, and before the hydraulic binder is cured. The specific gravity is 1.4, which is formed by pressure molding.
By using a lightweight concrete block having a size of 2.0 to 2.0, the sand has the effect that the synthetic resin foam beads are compressed and shrunk inside the hydraulic binder during pressure molding, in addition to the normal action as a fine aggregate. It is possible to manufacture a product which has a function of preventing, has a flat surface, is clean, and has no crack, and has high dimensional accuracy. Also, as a result of this,
Since a large amount of synthetic resin foam beads can be mixed in the interior of lightweight concrete, it is possible to manufacture a high-quality product that is light in weight and does not impair the appearance of the product.

According to the lightweight concrete block of claim 2, since the synthetic resin foam is substantially spherical, that is, the bead-like shape, the synthetic resin foam is unlikely to be crushed during kneading or press molding. Product dimensions are obtained. Further, since the particle size is small, a product having a uniform density can be obtained by being well mixed with a hydraulic binder such as cement.

According to the lightweight concrete block of claim 3, an economical and tough product can be obtained.

According to the lightweight concrete block of claim 4, a toughest and most economical lightweight concrete block can be obtained.

According to the lightweight concrete block of claim 5, by containing an appropriate amount of synthetic resin foam,
The weight can be reduced while maintaining the toughness.

According to the lightweight concrete block of the sixth aspect, by containing an appropriate amount of sand, the sand functions as a normal fine aggregate, and the external pressure at the time of pressure molding is synthetic resin foam. As a result of being effectively prevented from being transmitted to the body, it is possible to prevent the synthetic resin foam from compressing and shrinking, and to eliminate the expansion of the synthetic resin foam after releasing the pressure to obtain a product with a clean surface. .

According to the lightweight concrete block of claim 7, since the fiber reinforcing material is contained, it is possible to obtain a lightweight concrete block which is tough and has a high bending strength.

According to the lightweight concrete block of claim 8, the use of cement as the hydraulic binder provides advantages such as high strength, excellent water resistance, and relatively low cost.

According to the lightweight concrete block of claim 9, fly ash and / or blast furnace slag are used for alkali resistance measures when cement is used as a hydraulic binder, for improving surface properties and for improving long-term strength. Since the cement is contained in a predetermined amount, it is possible to make the cement a weak alkali, which makes it possible to obtain a lightweight concrete block having good surface properties, toughness, and bending strength.

According to the method of manufacturing a lightweight concrete block of claim 10, the pressure forming process of the lightweight concrete block of claims 1 to 9 applies a pressing force of about 50 kgf / cm.
Since it is a press molding process of ² or more, the pressing time can be relatively short and the molding can be performed smoothly,
In addition, it is possible to easily form a product having a complicated shape that is impossible by extrusion molding or the like.

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Claims (10)

[Claims] 1. A synthetic resin foam, water, a hydraulic binder, and fine aggregate such as sand are kneaded and pressure-molded before hardening of the hydraulic binder, and have a specific gravity of about 1.4. Lightweight concrete blocks that are between 2.0 and 2.0. 2. The lightweight concrete block according to claim 1, wherein the synthetic resin foam is beads having an average particle diameter of about 2 mm or less. 3. The lightweight concrete block according to claim 1, wherein polystyrene is used as the synthetic resin foam. 4. The lightweight concrete block according to claim 1, wherein the synthetic resin foam has a specific gravity of approximately 0.05 to 0.20. 5. The lightweight concrete block according to claim 1, wherein the obtained lightweight concrete block contains a synthetic resin foam in a volume of approximately 10 to 40%. 6. The lightweight concrete block according to claim 1, wherein the obtained lightweight concrete block contains fine aggregate such as sand having a volume of about 10 to 40%. 7. The lightweight concrete block according to claim 1, wherein the fiber reinforcing material is mixed in an absolute volume of approximately 0.1 to 0.6%. 8. The hydraulic binder is cement.
Lightweight concrete block of any of 7 to 7. 9. The fly ash and / or blast furnace slag is mixed in an amount of approximately 10 to 35% by weight of the cement weight.
Lightweight concrete block. 10. The pressure forming process of the lightweight concrete block according to claim 1, wherein a pressing force is approximately 5
A method for manufacturing a lightweight concrete block, which is a press forming process at 0 kgf / cm ² or more.