JPH028991B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses granulated blast furnace slag and gypsum hemihydrate as the main materials, and if necessary, reinforcing fibers such as glass fibers are added thereto to increase toughness, and furthermore, by adding a compounding material, that is, a reaction stimulant. , relates to a method for manufacturing fiber-reinforced slag gypsum composites that have quick hardening, high strength, and water resistance.In particular, the quick hardening properties enable production by continuous molding instead of the conventional batch manufacturing method. Make it a major feature. In recent years, as buildings have become taller, the method of constructing wall materials has been changing from a wet method to a dry method, and along with this, there has been a desire for a wall covering material that is inexpensive and easy to construct. Conventional wall lumber has the disadvantages that gypsum-based materials absorb a large amount of water and have extremely poor physical properties when water is absorbed, while cement-based materials have drawbacks such as poor impact strength. The present invention mainly consists of granulated blast furnace slag and gypsum hemihydrate, which are mixed in a weight ratio of 2:8 to 8:2, and inorganic fibers are added in an amount of 0.3 to 20% by weight based on the total weight of the main materials. %, and further add 0.5 to 20% by weight of Portland cement, 0.1 to 2.0% by weight of aluminum sulfate-containing substances, and 0.1 to 2.0% by weight of fluoride salts either singly or in combination. A suitable amount of water is added to make a slurry, which is continuously formed on a belt, solidified in 10 to 30 minutes, and heated to 50°C.
Wall covering material is continuously produced by heating, curing and drying at a temperature of ~200°C. The main materials constituting the composite material of the present invention, that is, the hardened material, are granulated blast furnace slag and gypsum hemihydrate. This is preferable because it allows for rapid setting and a cured product with high strength, but it is sufficient that the specific surface area is 3000 cm ² /g or more. An example of the chemical composition of slag from granulated blast furnaces is shown in Table 1.

[Table] There are two types of gypsum hemihydrate: α type and β type, which is generally calcined gypsum, and either of these can be applied. However, in the present invention, it is necessary to set the slurry for 10 to 30 minutes, and since the initial strength depends in part on the dihydration of gypsum hemihydrate, it must be made of gypsum hemihydrate. Compared to β-hemihydrate gypsum, α-hemihydrate gypsum can be mixed even with a smaller amount of water, so
The initial strength is higher than that using β-hemihydrate gypsum, but the reason why the hardened product obtained by the present invention shows high strength is that it is essentially a slag hydrate (CaO-SiO ₂ −Al ₂ O ₃ −nH ₂ O, etc.) and CaO−Al ₂ O ₃ −MgO−SiO ₂ which is the main component of slag.
Calcium sulfoaluminate hydrate (3CaO・
_Al2O3・_3CaSO4・_32H2O ) _.
Therefore, the use of α-hemihydrate gypsum has no effect on the essential strength of the cured product of the present invention. In order to be used as a general-purpose wall covering material, the raw materials used must be inexpensive and have a stable supply.
As raw materials for the composite material of the present invention, in addition to by-product gypsum such as flue gas desulfurization gypsum and phosphate gypsum as β-hemihydrate gypsum, there is no problem in using natural gypsum, a material generally called calcined gypsum. It is preferable to use inorganic fibers or carbon fibers as the reinforcing fibers that may be mixed into the main material if necessary, since it is necessary to make the composite material of the present invention a noncombustible material. Glass fiber, slag wool, asbestos, or the like can be used as the inorganic fiber. The composite material of the present invention uses alkaline granulated blast furnace slag as the main material, but it is possible to reduce the pH to 10 or less even during the reaction by using the blended materials described later. As the glass, alkali-free glass or low-alkali glass, generally called E glass, can be used. Addition of reinforcing fibers increases the bending strength of the cured product and significantly improves toughness, resulting in a material with excellent impact resistance. When glass fibers are used as reinforcing fibers, the physical properties vary depending on the length of the fibers, the amount added, or the degree of convergence of the strands.
The longer the fiber length, the better the reinforcing effect, but considering the difficulty and processability during molding, the fiber length should be 13 to 50 mm.
is appropriate. Addition amount is 0.3 to 7.0 to the main material
The weight percentage is appropriate, but this has a lot to do with the convergence of the strand, and if the convergence is small,
That is, when the degree of defibration is high, 0.3 to 3.0% by weight is appropriate; if the amount added is more than this, both the bending strength and the compressive strength will decrease. Portland cement, aluminum sulfate-containing substances, and fluoride salt substances are used as compounding materials, but their main purpose is to act as a reaction stimulant to promote the coagulation of granulated blast furnace slag, so these materials are used in the compounding process. Use one of the three types or a combination of two types. The Portland cement may be a commercially available ordinary Portland cement with a specific surface area of about 3000 cm ² /g. The amount added is 0.5 to the main material.
It is 20% by weight. The aluminum sulfate-containing substance may be aluminum sulfate, sodium alum, or potassium alum, and the amount added should be determined based on the main material.
It is 0.1-20% by weight. The fluoride salt substance may be sodium silicofluoride, potassium silicofluoride, sodium fluoride, or potassium fluoride, and the amount added should be determined based on the main material.
It is 0.1-20% by weight. Next, the cured product of the present invention can be molded by continuous extrusion because of its quick hardening properties. As a result, the size of the plate material can be freely changed depending on the width of the belt, and the uncured material obtained through continuous production can be
Dry for 15-48 hours in a hot air drying oven at a temperature of 200°C. According to the method of the present invention, the slurry is kneaded by controlling the added Portland cement, aluminum sulfate, fluoride salts, etc., and then shaped while maintaining fluidity on the belt for several minutes before being transferred to the belt for the next process. It condenses to a strength that allows it to be peeled off and carried, and is then further hardened by ettringite during heating and drying, so it has high strength, water resistance, and excellent processing methods, and uses inexpensive main materials. Its value as a building material is extremely large, as it can be used and produced continuously. Examples are shown below. However, the present invention is not limited to the following examples. Example 1 Main material consisting of 60 parts by weight of granulated blast furnace slag and 40 parts by weight of β-hemihydrate gypsum, 1.0% by weight of 25 mm chopped stranded glass fiber as reinforcing fiber,
Preparation materials: Portland cement 2.0% by weight as reaction stimulant, aluminum sulfate 0.2 or 0.6
Or add 1.0% by weight each and 60% by weight of water.
In addition, three types of samples No. 1 to No. 3 shown in Table 2 were prepared, and after kneading, the slurry was poured into a steel mold, molded, and dried at 60°C for 48 hours.
~The physical property values of No. 3 were determined, and these are shown in Table 3. Example 2 Main material consisting of 60 parts by weight of granulated blast furnace slag and 40 parts by weight of β-hemihydrate gypsum, 1.0% by weight of 25 mm chopped strand glass fiber as reinforcing fiber,
Portland cement 2.0% by weight, sodium silicofluoride 0.2 or 0.6 or 1.0% by weight as reaction stimulants
and 60% by weight of water to make the three types of samples No. 4 to No. 6 shown in Table 2. After kneading, the slurry was poured into a steel form and molded, and heated to 48°C at 60°C. After drying for a period of time, the physical properties of these cured products No. 4 to No. 6 were determined and are shown in Table 3.

【table】

[Table] Shows the compressive strength tested.
Example 3 To the main material consisting of 50 parts by weight of granulated blast furnace slag and 50 parts by weight of β-hemihydrate gypsum, 0, 0.4 or 0.8% by weight of sodium sulfate was added as a reaction stimulant, and 60% by weight of water was added. Samples No. 1 to No. 3 shown in Table 4 were prepared, and after kneading, the apparent setting time was measured using a Vicat needle device setting time measuring device, and the results are shown in Table 5. Example 4 Aluminum sulfate 0 or 0.4 or 0.8 or 1.2 or 1.6 or
2.0% by weight and 50% by weight of water to prepare samples No. 4 to No. 9 shown in Table 4, and after kneading, measure the apparent setting time with a Vicat needle setting time measuring device, This is shown in Table 5. As is clear from Figure 1, by using a reaction stimulant such as aluminum sulfate, the setting time of the blast furnace granulated slag gypsum composite can be reduced to within 20 minutes, and the production method using continuous extrusion molding is This shows that it is possible.

【table】

【table】

[Table] Gradually drop the starting needle into the slurry, and the starting point is when the tip of the needle stops approximately 1 mm from the top surface.To finish, drop the ending needle in the same way. It ends when it leaves no trace. That is, the time required for coagulation is the final time. Example 5 Seven main materials consisting of 20 to 80 parts by weight of granulated blast furnace slag and 80 to 20 parts by weight of β-hemihydrate gypsum were combined with 2.0% by weight of 25 mm chopped strand glass fiber as reinforcing fibers. , Portland cement 2.0% by weight as reaction stimulant, aluminum sulfate
0.4% by weight was added to each of the seven types of samples No. 1 to No. 7 shown in Table 6. To these, a predetermined amount of water shown at the end of Table 6 was added, and after kneading, the slurry was made into steel. After pouring into a mold and molding and drying at 60° C. for 48 hours, the physical properties of these cured products No. 1 to No. 7 were determined and are shown in Table 7.

【table】

[Table] Shows the compressive strength tested.

[Brief explanation of drawings]

Figure 1 shows 50 or 70 parts by weight of granulated blast furnace slag, β-
The main material consists of 50 or 30 parts by weight of gypsum hemihydrate, 60% by weight for the former and 50% by weight for the latter, and 0% aluminum sulfate as a reaction stimulant.
This figure shows the relationship between the amount of aluminum sulfate added and the coagulation time (apparent completion time) of the slurry when the aluminum sulfate is added in the range of ~2.0% by weight and kneaded.

Claims (1)

[Claims] 1 The main materials are granulated blast furnace slag and gypsum hemihydrate, which are mixed in a weight ratio of 2:8 to 8:2, and inorganic fibers are added to the total weight of the main materials.
Add 0.3 to 20% by weight, and further add 0.5 to 20% by weight of Portland cement, 0.1 to 2.0% by weight of aluminum sulfate-containing substances, and 0.1 to 2.0% by weight of fluoride salts, singly or in combination. A slurry is formed by adding an appropriate amount of water to the slurry, which is continuously molded on a belt, solidified in 10 to 30 minutes, and heated and cured at a temperature of 50 to 200 degrees Celsius to dry it. A method for producing a fiber-reinforced slag gypsum composite material characterized by: