JPS63282149A - Hydraulic composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which has excellent dispersibility, rapidly develops strength and yields cured matter of high strength by consisting said compsn. of blast furnace slag powder, alkali component and hydrous org. gel. CONSTITUTION:This hydraulic compd. is obtd. by compounding 0.5-20pts.wt. alkali component (e.g.: slaked lime), <=5pts.wt. hydrous org. gel obtd. by absorbing 5-1,000 times water in a highly water absorptive polymer (e.g.: starch/ acrylinitrile graft copolymer), and if necessary, aggregate, reinforcing material, water-reducing admixture, dispersant, air entraining agent, etc., with 100pts.wt. blast furnace slag powder, adding water to the mixture at 50-30wt.% of the weight of the entire hydraulic component and mixing the mixture. The molding of this compsn. is then packed in a form and is molded for >=1min under >=5kg/cm<2>, following which the molding is cured.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a novel hydraulic composition, and more particularly, to a hydraulic composition using blast furnace slag powder. (Prior Art) Blast furnace slag is It is a by-product during the production of pig iron and is used in landfills as industrial waste, but there are problems such as high processing costs. However, when blast furnace slag is rapidly cooled in water or air, it becomes glassy.
A powdered version of this hardens in the presence of an alkaline component. The property of having no hydraulic property by itself but hardening in the presence of alkaline components is called latent hydraulic property.Blast furnace slag powder takes advantage of this property and can be mixed with materials such as Portland cement, which liberates lime content through water use reactions. It is used as blast furnace cement.

(Problems to be solved by the invention) A combination of blast furnace slag powder and an alkaline component is
It has advantages such as low heat generation and high resistance to salt water, but it develops strength more slowly than normal cement compositions, and it takes a long time to reach a certain level of strength. There is a problem. For this reason, in the J Engineering S Standard for blast furnace cement, the mixing ratio of blast furnace slag in blast furnace cement is set at 70% or less.
Under these circumstances, in order to take advantage of the above-mentioned performance advantages of blast furnace slag, as well as its economic advantage of being inexpensive, a large amount of blast furnace slag powder is used to develop strength quickly, and There was a need for a method to obtain a cured product with high strength.

As a result of intensive studies to achieve these problems, the present inventors have discovered that an organic hydrous gel can be used as a water supply source when obtaining a hydraulic composition using blast furnace slag powder, an alkaline component, and water. We discovered that when used, a uniform curable composition with excellent dispersibility can be obtained, which can be cured with a low moisture content, and as a result, a cured product with quick strength development and high strength can be obtained. Based on this knowledge, we have completed the present invention.

(Means for Solving the Problems) According to the present invention, there is provided a hydraulic composition whose main components are blast furnace slag powder, an alkaline component, and an organic hydrous gel.

The blast furnace slag powder used in the present invention is produced by quenching slag (mine slag) obtained as a byproduct when producing pig iron by adding coke, limestone, etc. to iron ore and heating and reducing it in a blast furnace. Blast furnace slag is defined in JIS R5211, which is made into a powder that is porous and has silicic acid, calcium oxide, and alumina as its main components, but is not limited to this. It never happens.

The alkaline component used in the present invention can be any one that has been known to harden blast furnace slag powder having hydraulic properties, and is not particularly limited. Specific examples thereof include oxides or hydroxides of metals such as sodium, potassium, calcium, magnesium, and aluminum, and various cements that produce calcium hydroxide when subjected to a water-use reaction with water. Economically, slaked lime and Portland cement are advantageous. In the present invention, the amount of alkaline component is usually the amount required for the reaction of the latent hydraulic component, but it may vary depending on the required performance of the target product and its use. , is selected as appropriate. For example, when slaked lime is used as the alkaline component, the amount is usually 0.5 to 20 parts by weight per 100 parts by weight of blast furnace slag powder, and if it is more than this, problems will arise in the performance of the cured product. In addition, when using Portland cement as the alkaline component, usually
The amount is 1 part by weight or more and 40 parts by weight or less, and if it is used in an amount larger than this, it is economically disadvantageous.

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 gel-like organic material containing twice as much water may be used, and specific examples include starch-acrylonitrile graft copolymer systems, carboxymethyl cellulose systems, polyacrylonitrile systems, polyethylene oxide systems, and vinyl acetate-acrylic systems. Polyacrylic, a water-containing gel obtained by absorbing water into a highly water-absorbing polymer such as an acid salt copolymer system, a vinyl alcohol-acrylate copolymer system, a polyacrylate system, an olefin-maleic anhydride copolymer system, etc. Examples include hydrogels obtained by reacting polycarboxylic acid salts such as acid salts and olefin-maleic anhydride copolymer salts with a crosslinking agent in the presence of water.

The type of superabsorbent polymer mentioned above is not particularly limited, and any commercially available polymer can be used.

In the present invention, the amount of organic hydrogel to be mixed is usually an amount that can supply the amount of water used, but the amount is appropriately selected depending on the required performance of the target product and the intended use.

However, it is preferable to keep the amount of organic components constituting the hydrogel at less than 5x parts per 100 parts by weight of total hydraulic components.

Here, the term "all hydraulic components" refers to blast furnace slag powder and components that are hydraulic in themselves, such as Portland cement among those used as alkaline components.

In addition, the shape of the organic hydrous gel may be granular, plate-like, rod-like, etc., and the method of use is not particularly limited, but from the viewpoint of ease of mixing, it is preferable to use it as a granular gel.◎ The water used is: Although not particularly limited, usually tap water,
Groundwater, seawater, etc. are used.

The amount of water in the hydraulic composition of the present invention cannot be determined unconditionally because it varies depending on the materials used and its composition, but the upper limit is usually determined by the amount of total hydraulic components because the strength of the cured product cannot be reduced. It is 50% by weight or less, preferably 40% by weight or less.

Further, the lower limit of the amount of water used is not limited, but it is usually 5% by weight or more, preferably 10% by weight or more of the total hydraulic components. The lower limit of the amount of water is far less than the stoichiometric ratio of all hydraulic components, but the hydraulic components gradually form hydrates and are replenished with water required from outside during the curing period, etc. It is possible to produce a cured product with a small amount of water.

In the present invention, in addition to the blast furnace slag powder, alkaline component, and organic hydrous gel, commonly used aggregates and reinforcing materials can be appropriately blended as needed.

Specific examples of aggregates and reinforcing materials include lightweight aggregates such as sand, gravel, and perlite, weighted materials such as steel balls and perlite, gypsum, clay, clay, bentonite, lime, resin fibers, pulp fibers, carbon fibers, Examples include aramid fiber, metal fiber, glass fiber, asbestos, and wood chips.

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.

When such an admixture can be included in the superabsorbent resin in advance, it is preferable to use it in the superabsorbent resin.The mixing order in the present invention can be appropriately selected depending on the purpose of use of the target product. Specific methods include, for example, mixing blast furnace slag powder, alkaline components, and organic hydrous gel, and then mixing aggregate, reinforcing material, etc. as necessary; or mixing organic hydrous gel and aggregate in advance. rear,
Examples include a method of mixing blast furnace slag powder and an alkali component, and a method of mixing all materials at the same time. When mixing, a Hobart 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 obtained in this way can be Unlike ordinary slurry compositions, it is a mixture of solid particles. The method for curing this composition is not particularly limited, and methods such as pressure molding, vibration molding, and centrifugal molding can be used. For example, in the case of pressure molding, molding is performed by filling the composition into a mold and applying pressure.

Pressure is applied using a press, roller, roll, etc., and the pressure is not necessarily uniform depending on the composition of the hydraulic composition, but is usually 5'q/aa'' or more.Required for pressurization. Although the time is not necessarily constant depending on the pressure, composition, etc., it is usually preferable to continue applying pressure for one minute or more.In addition, in the case of vibration molding, after filling the mold, molding is performed by vibration.

After the molded composition is removed from the mold, if necessary, it is subjected to curing, if necessary.

The curing method is not particularly limited, and specific examples include water 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 curing progresses due to that water. However, if the amount of water in the hydrogel is less than the theoretical amount required for curing, curing is not necessary. The curing is completed by taking in moisture from the outside at this stage ◇ The cured product obtained in this way can be used for various purposes, but especially for panels, cement tiles, paving stones, slate, flooring, and blocks. It is useful as a secondary product such as.

(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 the parts in Examples, Comparative Examples, and Reference Side are based on weight unless otherwise specified. ◇Reference Example 1 Various super absorbent resins shown in Table 1 are made to absorb a predetermined amount of water to form a hydrogel (I). ) to (Ill) were obtained. Each of the obtained hydrogels was in the form of particles with a particle size of about 1 tom.

Table 1 Book l: manufactured by Nippon Shokubai Kagaku Co., Ltd., Aqualic *2: Sanyo Kasei Co., Ltd., Rip, Sunwet *3: manufactured by Kuraray Sobrene Co., Ltd., KI Gel Reference Example 2 Isobutylene-maleic anhydride copolymer (Claraysoprene Chemical Co., Ltd.) 75 parts of an 8% aqueous solution of polyethylene glycol diglycidyl ether (Kyoeisha Yushi Kagaku Kogyo ■Crack, Epolai) 400E) was added to 144 parts of an 8% aqueous solution of Sodium salt (neutralization degree 0.78), and the mixture was evenly distributed. After mixing, 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 perform a crosslinking reaction. The obtained hydrogel (■) is 50×5
It was a 0x10 dragon rectangular parallelepiped.

Example 1 Granulated blast furnace slag (cerament, Daiichi Cement Co., Ltd.) 1s
oor, cement (Asano Ordinary Portland Cement)
759, sand (Toyoura standard sand) 15752 and hydrogels (I) to (R') Hll in an amount corresponding to the water content shown in Table 2.
After kneading for 3 minutes using a Hobart type mortar mixer, the flow value was measured according to JIS R5201. The results are shown in Table 2.

Next, it was filled into a mortar mold of 5 crrLφ
After finishing the top surface of the molded product in accordance with 2.
The material was cured in water at 0°C until the specified age.

The compressive strength of the obtained cured product was determined according to JIS A 110B.
It was measured simply. The results are shown in Table 2.

For comparison, when water was used instead of the hydrous gel, the same procedure as in Example 1 was carried out, but the pressure operation was omitted), and the flow value and compressive strength of the obtained cured product were measured. The results are shown in Table 2.

Table 2; □□□□□□ - Moisture content per 100 parts of (blast furnace slag powder + cement) From this result, in the case of the present invention, it is possible to cure with a low moisture content, and the obtained It can be seen that the strength of the cured product is extremely high.

Example 2 The flow value and compressive strength were measured in the same manner as in Example 1, except that 575 liters of hydrogel (1), 150 liters of sand, and a predetermined amount of the alkaline component shown in Table 5 were added.

Also, for comparison, when water is used instead of the hydrous gel, the same procedure is performed, but the pressurization procedure is omitted)
, the flow value and the compressive strength of the obtained cured product were measured.

The results are shown in Table 6.

These results show that even if the type of alkali component is changed, curing can be achieved with a low moisture content, and the strength of the obtained cured product is extremely high.

Claims (1)

[Claims] Hydraulic composition mainly composed of blast furnace slag powder, alkaline component and organic hydrous gel