JPS5857387B2 - Rapid hardening cement composition - Google Patents

Description

Detailed Description of the Invention The present invention is an adduct of alumina cement mixed with lime such as calcium hydroxide, calcium oxide, dolomite plaster, etc., and an appropriate amount of glyoxal and sodium hydrogen sulfite, or biacetyl or biacetyl and hydrogen sulfite. A rapid hardening cement composition prepared by adding an adduct with sodium and a blend of two or more of these, or mixing aggregate and filler as necessary, and a bituminous emulsion or rubber added to the above rapid hardening cement composition. The present invention relates to a rapidly hardening cement composition containing latex or resin emulsion and a mixture of two or more thereof.

Alkali and alkaline compounds generally promote the setting of alumina cement, but acids and acidic compounds are known to have the effect of retarding this setting.

Dilute solutions of sulfur hydroxide, potassium hydroxide, calcium hydroxide and triethanolamine have an active setting accelerating effect on alumina cement, whereas magnesium hydroxide and barium hydroxide do not set due to their buffering action. It has the effect of delaying the

It is also known that addition of sulfuric acid at a low concentration causes rapid setting, whereas addition of hydrochloric acid or acetic acid at the same concentration slows down the setting of alumina cement.

It is also known that mixtures of Portland cement and alumina cement, or calcium hydroxide and alumina cement, etc. exhibit rapid setting properties, particularly at the following blending ratios.

In Western countries, this characteristic is used as a quick-setting material.

However, the rapid setting of the mixture of Portland cement and alumina cement has the disadvantage that the strength development in a short period of time is very low.

Furthermore, when mixing limes such as slaked lime and quicklime, instant setting is extremely difficult to handle without using special kneading machines and spraying machines.

Furthermore, a 2-ketogluconate such as 2-ketogluconic acid or its calcium salt or ammonia salt is added as a calcium ion sequestering agent to the alumina cement-lime based mixed cement to obtain a rapidly hardening cement composition with good strength development. is known from Japanese Patent Publication No. 44-4221.

A cement composition prepared by adding glyoxal to Portland cement for the purpose of improving its compressive strength and other physical properties is also known from US Pat. No. 3,365,319.

Furthermore, in order to delay the hardening of cement, β-keto acid esters, metal salts of β-keto acid esters, acetylacetone, glyoxal, and glyoxylic acid may be added as disclosed in JP-A-4959830. , glycerin, sucrose, wheat flour, casein, starch, cellulose, and hydroxycarboxylic acid salts have the effect of suppressing the hardening of mocement.
, Robson: High Alumina Cem
entsAnd Central Contract
ors Record Limited 1962. P,
125-129.

However, when these various additives are added to alumina cement-lime-based mixed cement, the setting time and hardening time are either too short or too long, resulting in inappropriate pot life, and therefore setting adjustment is required. Often the effect is not sufficient.

Furthermore, even when the setting control effect is good, the strength development effect is often insufficient, and there are very few additives that can satisfy both the setting control effect and the strength development effect.

In order to solve this problem, the present inventors took advantage of the well-known property that a mixture of alumina cement and lime exhibits instant setting properties, and further developed a technology that allows the mixture to freely adjust the setting time and hardening time. It has been discovered that by selectively adding possible additives, it is possible to obtain a rapidly setting cement composition having a pot life of 5 to 30 minutes (θ) and useful early strength, and as the additive. It has been confirmed that an adduct of glyoxal and sodium bisulfite, an adduct of biacetyl, an adduct of biacetyl and sodium bisulfite, and a mixture of two or more of these give particularly excellent results in terms of setting control effect and strength development effect. .

Table 1 shows the setting performance and hardening performance of compositions obtained by adding 1 part by weight of various additives to a cement prepared by mixing 80 parts by weight of alumina cement with 20 parts by weight of calcium hydroxide.

The water-cement ratio was 50% by weight in both cases.

Among the above test results, we particularly focused on the fact that glyoxal and sodium hydrogen sulfite alone had a small setting retardation effect, but their adducts had a large effect. and investigated their coagulation-regulating effects.

The test results are shown in Table 2.

The present invention was made based on the above experimental results, and consists of adding an adduct of an appropriate amount of glyoxal and sodium bisulfite, or addition of biacetyl or biacetyl and sodium bisulfite to a powder mixture of lime and alumina cement. A quick-hardening cement composition that is easy to handle and has excellent strength development by adding a compound or a mixture of two or more of these; , and the above rapid hardening cement composition, in which rubber latex or resin is mixed in place of the bituminous emulsion.

In the rapidly hardening cement composition of the present invention, since the mixing ratio of alumina cement and lime can be set to a fixed value in advance, a large amount of the mixture can be prepared in advance with an accurate mixing ratio, and it is possible to prepare a large amount of the mixture in advance at the desired ratio. The composition of the present invention can be easily obtained by adding a setting regulator depending on the pot life of the composition.

In carrying out the present invention, the mixing ratio of lime is 10 to
A range of 50% (by weight) is preferable, and a range of 20% is particularly excellent in terms of strength development.

If it is less than 101% or more than 301%, the initial strength will be low.

Furthermore, when the mixing ratio of lime increases, a large amount of mixing water is required to obtain a kneaded material with a desired viscosity, which is disadvantageous in terms of strength development.

In addition, the strength when the mixing ratio of lime is 20 yen is sensitively affected by the water-cement ratio, so water can be added depending on the desired strength, but at other ratios, the water-cement ratio must be reduced. It has been confirmed through experiments by the inventor that the strength does not increase significantly even if the

It has also been confirmed that changes in the mixing ratio of lime do not significantly affect the effectiveness of the setting regulator.

Among the setting regulators, the addition of biacetyl alone has the greatest setting retarding effect, and the amount added is preferably in the range of 0.1 to 2φ (by weight) to the mixed cement.

The setting retardation effect of the adduct of biacetyl and sodium bisulfite is slightly lower than that of biacetyl alone, but
The amount added is preferably in the range of 0.1 to 10 (by weight) to the mixed cement.

The addition of an adduct of glyoxal and sodium bisulfite is inferior in setting retardation effect compared to the above, but is superior in terms of strength development.

The amount added is preferably in the range of 0.1 to 10φ (weight).

As the bituminous emulsion, a bituminous material such as asphalt, tar, pitch, etc. is dispersed in water using a suitable emulsifier, emulsification aid, stabilizer, etc.

Furthermore, there are three types of emulsions depending on the type Q of the emulsifier: cationic type, nonionic type, and anionic type, and any type of emulsion can be used in the present invention.

Rubber latexes include natural rubber, styrene-butadiene rubber, butyl rubber, styrene-isobutylene rubber, acrylnitrile-butadiene rubber, chloroprene rubber, and other rubber latexes; resin emulsions include natural resins, vinyl acetate resins, and ethylene-vinyl acetate copolymer resins. ,
Resin emulsions such as acrylic acid ester resins can be used.

However, when using bituminous emulsions, comb latex, or resin emulsions, emulsifying base agents, It is adjusted by selecting and combining emulsification aids and stabilizers.

Generally, it is known that carboxylic acid, sulfonic acid, or organic compounds having hydroxyl groups are effective as setting retarders for cement, but in particular, all of them are effective as setting retarders for alumina cement-lime based mixed cement. However, what is suitable for practical use is limited.

It is also known that cement compositions contain certain dicarbonyl compounds, such as glyoxal, and that the setting time of cement compositions can be influenced by the addition of dicarbonyl compounds.

However, the specific effect of adding a dicarbonyl compound to an alumina cement-lime based mixed cement that exhibits instant setting phenomenon is not known.

Furthermore, it has been confirmed through the above experiments that compounds such as glyoxal, acetyl-butyrolactone, oxalic acid, malonic acid, acetylacetone, succinic acid, and geltaraldehyde have no significant effect.

When the present inventors conducted a comparative experiment between the setting regulator of the present invention and calcium 2-ketogluconate, the results shown in Table 3 were obtained.

From Table 3, (a) As the amount of calcium 2-ketogluconate added increases, the pot life increases, but the compressive strength tends to decrease.

(b) In the case of adducts of glyoxal and sodium bisulfite, the pot life increases when the amount added is up to 2.5 degrees, but it tends to become shorter when the amount exceeds that.

In addition, the compressive strength is maximum when the amount added is 1.
When the amount added increases to 2.5%, the compressive strength decreases, but when the amount added further increases, the compressive strength tends to increase.

Also, compared to the mixture of calcium 2-ketogluconate,
Its compressive strength has been greatly improved.

(/→ Biacetyl has a greater setting retardation effect than the above two, so it is possible to adjust the setting time by adding a small amount.

There is no big difference in the compressive strength development effect from calcium 2-ketogluconate.

As described above, the setting regulator of the present invention is significantly different from calcium 2-ketogluconate.

Adducts of glyoxal and sodium bisulfite are effective in developing strength, and biacetyl and adducts of biacetyl with sodium bisulfite are effective in increasing pot life.

Therefore, the setting control agent can be selected depending on the desired strength and pot life.

Although the rapid hardening cement composition that is the object of the present invention can be applied to various uses, it has a very short pot life compared to other cement compositions, so it has not been used in the past. Rather than applying it to concrete work at construction sites and precast concrete panel materials, by combining the characteristics of rapid hardening and known technology, (1) It can be advantageously used as a repair material inside fire towers of coke facilities.

In other words, it is difficult to secure enough construction time for repair work inside the fire tower due to production constraints, and repair work is usually carried out between coke extinguishing work.

Additionally, since acidic water vapor is diffused, acid-resistant repair materials are required.

The rapidly hardening cement composition of the present invention is very useful because it contains acid-resistant alumina cement as a main component.

In addition, in the rapidly hardening cement composition of the present invention, the mixing of a synthetic resin emulsion is effective in improving the adhesion with the base concrete and the acid resistance, and the mixing further extends the pot life of the kneaded product ( (See Example-(3)).

Further, aggregate and filler may be mixed as necessary.

Other useful uses of the rapidly hardening cement composition of the invention are as follows.

(2) Existing finishing materials can be used as emergency repair materials.

For example, a ceramic tile that has suffered damage such as cracking or peeling can be removed, a new tile can be laminated with the rapidly hardening cement composition of the present invention, and it can be used as usual one hour after installation.

Also, mixing synthetic resin is effective in improving adhesion with the underlying concrete.

(3) It can be used as a base conditioner for wet concrete bases of coating materials such as resin-based flooring materials.

Floor coating materials such as epoxy resin and urethane resin cannot be applied if the underlying concrete is wet.

The rapid hardening cement composition of the present invention mixed with an appropriate amount of emulsion is applied to a wet concrete base to a thickness of one coat or more.

If the amount of concrete to be used is large due to irregularities in the base concrete, aggregate may be mixed in as a filler.

Since this base conditioner hardens in a short time and the surface dries, plastic flooring material can be applied one hour after the base conditioner is applied.

In addition, when a synthetic resin emulsion is mixed, the adhesion with the base concrete improves and an impermeable layer is formed, so the floor covering will not peel off due to moisture from the base concrete (see Example (5)). .

(4) It can be used as a filler to stop water leaking in underground structures, tunnels, etc.

Although it is technically difficult when the amount of water leakage is large and severe, when the amount of water leakage is small, the defective parts such as cracks and joints are V-cutted and the rapidly hardening cement composition of the present invention is crimped. It is possible to stop water by

(5) It can be used as a material to strengthen the consolidation of the ground and rock, and as a water-stopping material.

(6) By mixing a bituminous emulsion, rubber latex, or synthetic resin emulsion into the rapid hardening cement composition of the present invention, it can be used as a grout material having rapid hardening and stress relaxation properties.

(See Example-(6)). Next, examples will be shown.

Examples (1) The mixtures shown in Table 4 were kneaded to produce cement mortar with rapid hardening properties.

Their pot life and compressive strength after 1 hour are shown in Table 5.

However, an adduct of glyoxal and sodium bisulfite was used as a coagulation regulator.

Example (2) The mixtures shown in Table 6 were kneaded to produce a cement paste having rapid hardening properties.

Their pot life and 1 hour compressive strength are shown in Table 7.

Example (3) The mixtures shown in Table 8 were kneaded to produce a cement paste having rapid hardening properties.

The pot life and compressive strength after 1 hour are shown in Table 9.

Example (4) Kneading the mixture shown in Table 10, Has rapid hardening* *I made cement paste.

The pot life and compressive strength after 1 hour are shown in Table 11.

Example (5) A rapidly hardening kneaded material obtained in the same manner as in Example (3) was applied to a thickness of about 1 mm on the smooth surface of a wet asbestos slate board (15CrrLX 30 cm, thickness 2.5 cm). Ta.

After 30 minutes of application, an iron attachment (4CIfL x 4CIrL) was pasted with ultra-fast curing epoxy ◇* resin, and after 1 hour and 24 hours of kneading of the rapid hardening cement composition.
After a period of time, an adhesion test was conducted using a Kenken tensile tester.

The results are shown in Table 12.

Example (6) The mixtures shown in Table 13 were kneaded to produce a grout material having rapid hardening properties.

Its pot life, compressive strength and elastic modulus are shown in Table 14.

Claims (1)

[Claims] 1 Alumina cement or a mixture of alumina cement and aggregate and/or filler with lime, adducts of glyoxal and sodium bisulfite, biacetyl and adducts of biacetyl and sodium bisulfite A rapidly hardening cement composition characterized by adding one or more of these. 2 Alumina cement or a mixture of alumina cement, aggregate and/or filler with lime, and either one or two adducts of glyoxal and sodium bisulfite, biacetyl, and adducts of biacetyl and sodium bisulfite. with the addition of more than one
A rapidly hardening cement composition comprising one or more of a bituminous emulsion, a rubber latex, and a resin emulsion.