JPS63319238A - Novel hydraulic composition - Google Patents

Abstract

PURPOSE:To produce the title novel hydraulic composition having excellent dispersibility and capable of providing high-strength cement by mixing cement, superfine powder, and aggregates with the use of an org. hydrogel. CONSTITUTION:Cement (ordinary cement, etc.), superfine powder, aggregates (river sand, etc., having >=about 6 Mohs' hardness), and an org. hydrogel are mixed to prepare a composition. In addition, the superfine powder such as silica dust having <=about 10mu mean particle diameter is used, and 3-40pts.wt. of the powder is mixed with 100pts.wt. cement. A starch-acrylonitrile graft copolymer-based gel, etc., contg. water in the amt. of about 5-1,000 times its own weight is used as the org. hydrogel, the amt. is controlled to about 5-35pts.wt., based on 100pts.wt. of the cement plus superfine powder, and the amt. of the org. component is adjusted to <=about 5pts.wt., based on 100pts.wt. of the cement plus superfine powder. The composition is a uniform mixture having excellent dispersibility, and a high-strength mortar or concrete product can be obtained by molding and curing the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a novel hydraulic composition, and more particularly to a novel hydraulic composition that has excellent dispersibility and provides a high-strength cement product.

(Conventional technology) Cement products such as mortar and concrete are used in civil engineering and
It is widely used as a material for building structures, but as structures become longer and taller, there is an increasing need for high-strength cement products.

One way to improve the strength of cement products is to increase the strength of cement yeast by lowering the water/cement ratio.

This water/cement ratio can be reduced by using a high performance water reducer.
Therefore, it is possible to reduce it to about 0.3.

However, on the other hand, in order to maintain kneading and workability when raising mortar or concrete, a certain amount of water is required per unit volume of mortar or concrete. Therefore, in order to maintain the water/cement ratio of mortar or concrete and maintain fluidity, the amount of cement per unit volume ab of mortar or concrete is increased. However, this method has the problem that the cement product cracks due to the increase in calorific value accompanying the increase in the amount of cement, and is also economically disadvantageous. Furthermore, since a large amount of high-performance water reducing agent is used, the slump value fluctuates greatly due to a small change in the amount of water, the slump value changes significantly over time, and the mortar has good fluidity, making it easy for aggregate separation to occur. There are also many problems with construction management.

In addition, as another method for improving the strength of cement products, a method has been proposed in which calcium sulfate or ultrafine powder is mixed with cement to reduce the voids in mortar or concrete (Japanese Patent Laid-Open No. 61-21953, 6l. -247
651). However, even with this method, it is necessary to increase the amount of cement per unit volume of mortar or concrete and use a high-performance water reducing agent, resulting in the above-mentioned cracking of the cement product, economical issues, and construction management issues. The above problem is not resolved.

(Problem to be solved by the invention) Therefore, there is a need for a method of obtaining a high-strength cement product by keeping the water/cement ratio small without increasing the amount of cement per unit volume of mortar or concrete. was.

As a result of intensive research to achieve this problem, the inventors of the present invention found that
By mixing cement, ultrafine powder, and aggregate using organic hydrous glue as a water source, a homogeneous mixture with excellent dispersibility can be obtained, which can be shaped and hardened. The present inventors have discovered that a mortar or concrete product with high strength can be obtained, and based on this knowledge, they have completed the present invention.

(Means for Solving the Problems) Thus, according to the present invention, there is provided a novel hydraulic composition characterized by containing cement, ultrafine powder, aggregate, and organic hydrogel.

The cement used in the present invention is not particularly limited, but usually, ordinary cement, early-strengthening cement, ultra-early-strengthening cement, or Lutran F cement such as white cement is used. Sara K.

Bulky cement, mixed cement containing blast furnace slag, fly ash, etc. can also be used.

The ultrafine powder in the present invention is 10#m or less, preferably 1
It is a powder whose main constituent is one or more metal oxides and has an average particle diameter of μm or less. As a specific example, silica dust such as silica dust (silica dust) which is produced as a by-product during the production of fluorosilicon etc. is particularly suitable, but silica dust such as rehydrated calcium oxide, silica gel, titanium oxide, aluminum oxide, and minerals are particularly suitable. You can also use finely crushed silica stone.

The amount of ultrafine powder added in the present invention is 3 to 40 parts by weight, preferably 5 to 35 parts by weight, per 100 parts by weight of cement. If it is less than 3 parts by weight, there is no effect of increasing the strength;
Even if more than 0 parts by weight is mixed, higher effects cannot be expected and it is economically disadvantageous.

The aggregate used in the present invention may be one that is normally used in mortar or concrete, and specific examples include ordinary river sand, river gravel, mountain sand, mountain gravel, crushed stone, crushed sand, and sea sand. . Particularly when high-strength cement is required, it is desirable to use hard aggregate with a Mohs hardness of 6 or higher, preferably 7 or higher.

On the other hand, the organic hydrogel used in the present invention contains a large amount of water,
For example, 5 to 1000 times its own weight, preferably 10 to 800 times
Any glue-like organic substance containing twice as much water may be used, and specific examples thereof include starch-acrylonitrile graft copolymer system, cal? oxymethylcellulose, polyacrylonitrile, polyethylene oxide, vinyl acetate-acrylate copolymer, vinyl alcohol-acrylate copolymer, polyacrylic
High water absorption such as acid salt system, olefin-leic anhydride copolymer system, etc.? Water-containing glue obtained by absorbing water in a rimmer? Examples include hydrous glues obtained by reacting I-lycarginates such as lyacrylates and olefin-maleic anhydride copolymer salts with a crosslinking agent in the presence of water.

Highly absorbent as above? There are special restrictions on the type of rimmer, but any book that is generally available on the market can be used.

In the present invention, the amount of organic water-containing glue to be mixed is normally sufficient as long as it can supply the amount of water used, and the amount is appropriately selected depending on the required performance and usage of the target product, but 5 to 35 parts by weight per 100 parts by weight,
Preferably it is 10 to 30 parts by weight. In addition, the amount of organic content constituting the water-containing glue is 10 in total, including cement and ultrafine powder.
It is preferable to keep the content at 5 parts by weight or less relative to 0 parts by weight.

Further, the shape of the organic water-containing gel is not particularly limited, such as granules, plates, rods, etc., and the method of use is not particularly limited, but it is preferable to use it as a granular gel from the viewpoint of ease of mixing.

The water used is not particularly limited, but usually tap water,
Groundwater and seawater are used.

In the present invention, in addition to cement, ultrafine powder, aggregate, and organic hydrous gel, fibrous reinforcing materials such as steel fibers, glass fibers, and carbon fibers can be added as necessary.

Furthermore, an admixture can be added as necessary. Specific examples of admixtures include water reducing agents, binders, dispersants,
Air entraining agents, wetting and dispersing agents, swelling agents, waterproofing agents, strength enhancers, curing accelerators, curing retarders, setting accelerators, setting retarders,
Examples include thickeners and the like.

If such an admixture can be included in the superabsorbent resin in advance, it is preferable to include it in the superabsorbent resin.

The mixing order in the present invention can be appropriately selected depending on the intended use of the target product. Specific methods include, for example, mixing cement, ultrafine powder, and organic hydrous gel, and then mixing aggregate and, if necessary, supplements and reinforcing materials.
After mixing organic hydrous gel and aggregate etc. in advance, cement,
Examples include a method of mixing ultrafine powder and a method of mixing all materials at the same time. When mixing, a honokuto mixer, a tilting mixer, a forced kneading mixer, etc. are usually used, but there are no particular limitations.

The hydraulic composition of the present invention thus obtained is a mixture of solid particles, unlike a typical slurry composition fluidized with water. The method for curing this composition is not particularly limited, and methods such as pressure molding, vibration molding, and centrifugal molding may be applied. For example, in the case of pressure molding, molding is performed by filling a mold with the composition and applying pressure.

Compaction methods include centrifugal molding, which utilizes centrifugal force and is commonly used in the manufacture of hydraulic products. These compaction methods may be combined as appropriate. As an example, a method can be shown in which a mixture is filled into a mold, subjected to vibration and then pre-pressurized, and further subjected to vibration again and then pressurized and molded.

The time required for compaction is not particularly limited as long as it is possible to make a mold, and depending on the compaction method, composition, etc., it may not necessarily take a certain amount of force, but it is usually preferable to continue compaction for 30 seconds or more.

The molded composition is removed from the mold, if necessary, and then subjected to curing, if necessary.

The curing method is not particularly limited, and specific examples include underwater curing, humid air curing, steam curing, and autoclave curing.

In the case of the present invention, the water in the hydrogel gradually oozes out during curing, and the hardening progresses due to the moisture, but if the amount of water in the hydrogel is slightly lower than the theoretical amount required for curing, At this stage, moisture is introduced from the outside to completely cure the book.

The thus obtained cured product can be used for various purposes, but is particularly useful as secondary products such as nonel, cement tiles, paving stones, slate, flooring materials, blocks, etc.

(Effects of the Invention) Thus, according to the present invention, by using an organic hydrogel as a water supply source, it has good dispersibility and can be cured with a low water content, resulting in excellent quality and economic efficiency. A hydraulic composition that provides a cured product can be obtained.

(Example) The present invention will be described in more detail with reference to Examples below. Note that parts in Examples, Comparative Examples, and Reference Examples are based on weight unless otherwise specified.

Reference Example 1 Hydrogels (1) to (1) were obtained by absorbing a predetermined amount of water into various superabsorbent resins shown in Table 1. Each of the obtained hydrogels had a particle size of 1 m.

Table 1 *1: Manufactured by Nippon Shokubai Kagaku Co., Ltd., Aqualink Book 2: Manufactured by Sanyo Kasei Co., Ltd., Sunwet Co., Ltd., isopane 10) sodium salt (
Polyethylene glycol diglycidyl ether (manufactured by Kyoeisha Yushi Kagaku Kogyo Co., Ltd., Epolite 400E') 8% aqueous solution 73
The mixture was poured into a stainless steel container, sealed to prevent moisture from evaporating, and heated in an oven at 60° C. for 2 hours to carry out a crosslinking reaction. The obtained hydrated glue (
IV) was a rectangular parallelepiped of 50 x 50 x 10 m''.

Example 1 Cement (Asano Ordinary Portland Cement) 100
ON, silica fume (manufactured by Nihon Heavy Chemical Co., Ltd., average particle size 0.1 μm) in the amounts shown in Table 2, silica sand (particle size 5 μm or less) 2
000# and water-containing glue (1
) ~ (■) and mix with a Hobart type mortar mixer.
Kneaded for a minute. The obtained mixture was divided into 5ct11φ×10
Filled into the formwork for mortar of Tan, the vibration frequency is 300 orpm,
After vibrating for 1 minute on the vibration table of Shake@IIIK, pre-pressurize with a surface pressure of 30 ky 7cm", further vibrate for 1 minute, and pressurize with a surface pressure of 100 kg / 7cm" to create a molded product. did. This product was cured overnight in a humid atmosphere at 20°C, and the upper surface of the molded product was finished according to JIS A 1132, and then removed from the mold and cured in water at 20°C to a specified age.

The compressive strength of the obtained cured product was measured according to JIS A 1108. The results are shown in Table 2.

For comparison, the same operation as in Example 1 was carried out in the case where water was used instead of the water-containing glue, and the compressive strength of the obtained cured product was measured. The results are shown in Table 2.

This result shows that in the present invention, by using an organic hydrogel, the compound can be uniformly dispersed with a low water content, and a cured product with extremely high strength can be obtained.

Example 2 After mixing according to the concrete composition shown in Table 3,
The mixture was kneaded for 3 minutes using a tilting mixer. 15kl of concrete obtained? Formwork for centrifugal molding (200H x 300
tx) K, and centrifugal molding was performed at 6G for 4 minutes, followed by 20G for 5 minutes. After molding, leave for 4 hours,
The temperature was raised to 75°C over a period of time, and then left at this temperature for 4 hours, then allowed to cool overnight and demolded. The obtained molded product was cured at room temperature, and the compressive strength at 7 days of age was measured.

For comparison, slurry formulations were prepared according to the formulations shown in Table 3 using a high performance water reducing agent according to a conventional method. This mixture was subjected to centrifugal molding and post-treatment in the same manner, and the compressive strength of the molded product was measured. 4th result
Shown in the table.

These results show that in the present invention, by using an organic hydrogel, the compound can be uniformly dispersed with a low moisture content, and a cured product with extremely high strength can be obtained with a small amount of cement. .

Claims (1)

[Claims] 1. A novel hydraulic composition containing cement, ultrafine powder, aggregate, and organic hydrogel