JPS59203755A - High strength lightweight concrete and manufacture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high-strength, lightweight concrete and a method for producing the same.

Conventionally, methods for obtaining lightweight concrete by room-temperature and normal-pressure molding include the aerated concrete forming method, in which a foaming agent is added to cement, foamed, and then poured, and the lightweight concrete method, in which lightweight aggregate such as shirasu balloons is processed and mixed with cement and solidified. There are material forming methods, etc. However, it is not possible to obtain lightweight and high-strength concrete by these methods. Therefore.

In order to obtain lightweight and high strength concrete.

After obtaining a cement molded body by the above-described method, it was necessary to perform an autoclave treatment using high-pressure steam. However, this autoclave treatment requires complicated equipment, and there are limitations on the size and shape of molded bodies that can be treated.

This method has many problems such as restrictions on the places where it can be processed. In addition, although the concrete obtained through this autoclave treatment is certainly high strength and lightweight,
The water absorption rate was approximately 30% by volume, and the water resistance was extremely poor.

The present inventors took into consideration the conventional problems as described above.

In order to solve this problem, various researches were conducted and the present invention was completed.

An object of the present invention is to provide a high-strength and lightweight concrete and a method for producing the same.

That is, the high-strength lightweight concrete of the present invention is characterized by being made by mixing cement, glass foam particles containing 10 or more parts of NagO, carbon dioxide gas, and water.

This concrete uses the above-mentioned Na as a raw material.
Since foamed glass particles containing No. 20 and carbon dioxide gas were used as the aggregate, the concrete had high strength and was lightweight. Also, this concrete.

Water absorption rate is low.

In addition, the high-strength lightweight concrete of the present invention has Na
It is manufactured by mixing glass foam particles containing 10% by weight or more of 2O and carbon dioxide with cement and water, and curing the mixture.

This production method makes it possible to obtain high-strength and lightweight concrete. In addition, high-strength lightweight concrete can be easily obtained at room temperature and pressure without taking any special measures to increase the strength. In addition, since foamed glass particles containing carbon dioxide gas and soda are used as the aggregate, an excellent early strength effect can be obtained.

The following 1. By using the high-strength lightweight concrete of the present invention and the sorter glass foam granules containing carbon dioxide gas, which are made by sufficiently foaming the glass, as aggregates.

We have achieved high strength and lightweight concrete--8
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Conventionally, when soda glass was used as an aggregate in Portland cement, the glass was soaked in calcium, which is a cement alkali, and reacted with the cement to crystallize.
This causes concentrated stress in the glass, reducing the strength of the glass, so it was thought that soda glass could not function as an aggregate. However, the present invention has solved this problem.

That is, the sorter glass foam particles in the present invention are very lightweight, and when mixed with cement.

■ The role of alleviating the elution of soda and promoting the hardening of concrete after the pot life, ■ The role of releasing the concentrated stress that occurs when hydrate crystallizes due to the reaction between cement and soda glass foam particles, ■ The role of cement It plays the role of entangling the crystals generated by the reaction of hydrates and cement with the glass foam particles, and causing an exothermic and water-absorbing reaction with the soda carbonate contained in the glass foam particles, resulting in early strength development. Therefore, by using these foamed soda glass granules as aggregate-4-, high-strength and lightweight concrete can be easily obtained at room temperature and pressure without any special post-treatment (for example, heat treatment).

Here, as the cement used in the present invention, ordinary Portland cement, alumina cement, or the like is used.

In addition, sorter glass foam particles contain 10% by weight of Nano.
Granular soda glass made by sufficiently foaming soda glass containing the above with carbonate, etc.

It contains carbon dioxide gas. The foamed glass particles may also be obtained by incorporating carbon dioxide gas in advance into a lightweight aggregate such as volcanic lapilli, and coating the aggregate with soda glass such as water glass. These soda glass foam beads are NagO
It is preferable to contain 10% by weight of 1ν or more. This is when mixed with cement.

This is because high-strength concrete can be obtained.

Further, it is preferable that the carbon dioxide gas contained in the sorter glass foam particles is 8% by volume or more. This is because the resulting concrete exhibits strength and increases its strength due to the water absorption effect. Also.

The glass foam particles preferably have nine spherical bodies and are mainly composed of closed cells. This is because it is easy to knead and workability is good when the 9-spherical body is used, and when there are many open cells.

This is because the water absorption rate becomes high and there is a possibility that a product with high strength cannot be obtained. Further, the foamed soda glass particles may be hollow.

Further, it is more preferable that the glass foam particles have a particle diameter of 05 to 60 fins. This means that the smaller the particle size, the more Na
The diffusion distance of sodium (sodium) into the cement is shortened and uneven hardening of the cement does not occur.
This is because if it is less than 5111, the water-cement ratio (W/C) increases and there is a risk that the strength will decrease by 1. In addition, when covering OHM, the gaps between the nine grains become large, and there is a risk that they may remain as voids in the concrete.

Further, it is more preferable that the foamed soda glass particles have a bulk specific gravity of 02 to 0.6. this is.

If it exceeds 0.6, it is not preferable from the viewpoint of weight reduction, and if it is less than 0.2, there is a possibility that the effects of the present invention may not be sufficiently achieved.

Here, the mixing ratio of cement and foamed soda glass particles is preferably such that the volume ratio of foamed soda glass particles to 1-1 cement is 1.5 to 4.5. Here, 1
The reason why the mixing ratio is set to be 5 or more is because if the mixing ratio is less than -5, the specific gravity becomes large and weight reduction cannot be achieved, and 4.
This is because if it exceeds 5, the relative amount of cement is small, which tends to cause communicating holes to occur in the concrete molded body, which may lead to a decrease in strength.

Moreover, water is more preferable as the kneading water used when mixing the cement and the foamed soda glass particles. Also.

Add an admixture as appropriate depending on the purpose. For example, by adding a small amount of a foaming agent, it is possible to assist in the dispersion of cement and soda glass foam particles, improve workability, or improve the hardness of the surface of a concrete molded body. The amount of kneading water used is preferably 0.20 to 0.87 per liter of cement in volume ratio. Is this a ratio compared to conventional usage? -,,- By keeping it within this relatively small range, it is possible to further improve workability, obtain high strength, and further reduce dimensional changes due to material age, resulting in highly accurate concrete. This is because it can be done. In addition, it is more preferably 0.27 to 088.

The high-strength lightweight concrete of the present invention can be obtained by mixing the above-mentioned cement, glass foam particles, and water, and curing the mixture. Although it is not yet fully clear that high strength can be obtained by hardening these raw materials, it is possible to obtain high strength by using glass foam particles containing 10 or more NayO and carbonate as an aggregate. , in the mixing and forming process of cement, the glass foam particles, and water.

The NS in the soda glass is purposely eluted to accelerate the hardening of the cement after the pot life expires, and the soda glass itself becomes Nm.
*COs・10H20 reduces the water-cement ratio (W/C) and at the same time accelerates hardening through an exothermic reaction, and also improves strength due to entanglement of cement and crystals formed between cement and glass -8- I think that the.

Further, the relationship between cement material and demolding is 9. For example, when ordinary Portland cement is used, demolding is possible after about 16 hours at room temperature. Also.

It can be demolded in about 4 hours by steam curing at 80°C.

In addition, when early strength cement is used, it can be demolded in about 4 hours by steam curing at 40°C.

In this way, conventionally it was impossible to remove the mold for a short period of time without using expensive cement (e.g. jet cement), but the manufacturing method of the present invention allows even low-cost cement to be used by appropriately selecting the cement material. It can enable demolding for a short period of time.

An example of the present invention will be shown below.

Example 1゜Portland cement, soda glass foam particles, and water were mixed in the proportions shown in Table 1, and IO×10XI (11
The concrete was cast into a mold, cured in a room at 18° C. for 16 hours, and then removed from the mold to obtain a hardened concrete body. After 14 days, the physical properties shown in Table 2 were measured for the cured product.

In addition, as a comparative example, a concrete hardened body was created by demolding after curing at room temperature for 8 days using a conventional method for obtaining lightweight concrete using the mixing ratio shown in Experiment No. CI in Table 1 (Experiment No. CI). Table 2 also shows the physical properties of the hardened concrete that were measured 80 days after demolding.

As is clear from Table 1-11--112-2, the concrete of the present invention is:
It can be seen that it is lightweight and has high strength.

Furthermore, it can be seen that this high strength and light weight can be easily obtained at normal temperature and normal pressure without using special measures such as an autoclave.

Furthermore, the high-strength lightweight concrete of the present invention obtained in 9 Examples has a very low water absorption rate.

It is also clear that the concrete has excellent freeze-thaw resistance.

Furthermore, the dimensional change over time is very small.

Example 2 Raw materials were mixed at a mixing ratio of 375 soda glass foam particles and 88 water α to 1 liter of ordinary bolt sand cement,
After curing indoors for 16 hours, the mold was removed to obtain a hardened concrete body. The strength development of the hardened concrete body is shown in A of FIG. In addition, the vertical axis in FIG. 1 represents the final strength, the strength development rate (%) relative to the degree, and the horizontal axis represents the age (days), respectively.

In addition, as a comparative example, the same figure shows the strength development of a hardened concrete obtained by kneading a raw material containing 80% perlite and 04% water to 1 liter of ordinary Portland cement and curing it indoors. It is also shown in B.

As is clear from FIG. 1, it can be seen that the concrete of this example according to the present invention develops its strength very quickly.

Example 8 Ordinary Portland cement (experiment numbers 8 to 7), expanded sorter glass grains, water, and additives were kneaded and mixed in the proportions shown in Table 8 using an omni mixer.

It was poured into a 10XIOXIOQ11 mold, cured in a room at 18°C for 16 hours, and then removed from the mold to obtain a hardened concrete body. The physical properties of the cured product shown in Table 4 are as follows.
ljll was determined.

In addition, when early-strength cement was used as the cement (experiment number 8), a hardened concrete was obtained under the same conditions as above, except that it was steam-cured at 60° C. for 4 hours. The physical properties of the cured product are also shown in Table 4.

As is clear from Table 4, it can be seen that the concrete of this example according to the present invention is a high-strength and lightweight concrete.

It also has a low water absorption rate and is a water-resistant concrete.

Table 8 Table 4 Table 5 - Example 4 A mixture of all raw materials (0) in which 1 part of ordinary Portland cement was mixed with 6.75 parts of foamed soda glass particles and 0.31 parts of water, and 1 part of ordinary Portland cement. Tenryoku O8A is added as an expanding agent to the raw materials with a blending ratio of grains 6.0 and water 033.
A mixture of 5% (D)'fr was cured at room temperature for 16 hours and removed from the mold to obtain concrete 1/hardened product.

As a comparative example, raw materials were mixed at a ratio of 6.9 perlite and 0.6 water to 1" of ordinary Portland cement (L'!)', which was cured at room temperature for 3 days, demolded, and made into concrete. A cured product was obtained. The dimensional changes of these three molded bodies (0, D, IN) are all shown in Figure 2.

As is clear from FIG. 2, the dimensional change rate of the concrete of the present invention is very small.

Example 5 Ordinary Portland cement, foamed soda glass grains, water, and additives were mixed in a tilting mixer in the proportions shown in Table 5, and a diameter of 10 (?F71 x length 20147) was mixed.
The concrete was poured into a No. 71 formwork, cured in a room at 18°C for 16 hours, and then removed from the mold to obtain a hardened concrete body. All physical properties shown in Table 6 were measured for the cured product.

In addition, the same table also shows a comparative example in which a cured concrete body was prepared by removing the mold by curing at room temperature for 3 days using the conventional method of obtaining lightweight concrete IJ-1-i with the mixing ratios shown in 02 to c5 in Table 5. Regarding (c2 to a5) / Table 6 Example 6 Ordinary Portland cement, soda glass foam preform, water, sand or volcanic stone were mixed in the proportions shown in Table 7. Mix and mix with mixer, 10X10×10c
Pour it into a mold of m and mold it from 16:00 to 20:00.
- Cured in a room at 18°C for one hour and removed from the mold to obtain a hardened concrete body f:. The physical properties shown in Table 7 were measured for the cured product.

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[Brief explanation of drawings]

The figure shows an example, and FIG. 1 is a diagram showing the relationship between concrete age and strength development rate in the second example.
The figure is a diagram showing the relationship between the age of concrete and the rate of dimensional change in the fourth example. A, O, D-・Invention E, E...Comparative example Patent applicant Co., Ltd. Toyota Central Research Institute Toyota Boshoku Co., Ltd. --22-

Claims (1)

[Scope of Claims] ill A high-strength lightweight concrete characterized by being made by mixing cement, 10% by weight or more of Naff0, fuss foam particles containing carbon dioxide gas, and water. (2) Glass foam particles have a particle size of 0.5 to 6. OI
ff. lsl Glass foam particles containing 10% by weight or more of Na@O and carbon dioxide gas, cement and water are mixed,
A method for producing high-strength lightweight concrete, which comprises curing these materials. (4) The method for producing high-strength lightweight concrete according to claim (8), characterized in that carbon dioxide is contained in the glass foam particles in an amount of 84% by volume or more. (5) The mixing ratio of cement, glass foam particles, and water is 15 to 4 glass foam particles to 1 part of cement (by volume).
, 5 water is 0.2 to 0.87.