JP2684226B2 - Cure for hydraulic substances - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a water-based material which is effective for preventing cracks in water-based materials, making it difficult to absorb water, making it water repellent, strengthening it, suppressing whitening, etc. Curing method for hard materials.

[Prior Art and its Problems] First, words used in the present invention will be described. In the present invention, the hydraulic material means concrete, mortar, and calcium silicate, which are hardened by hydration or hydrothermal reaction, among calcium-based uncured materials or hardened materials, gypsum-based and / or magnesia-based, alumina. Cement-based, gypsum-slag-based, slag-gypsum-slaked lime-based, and slag-
A generic term for hydraulic substances excluding slaked lime. The white flower component is an alkali mainly composed of calcium hydroxide produced when water is added to cement. Reactive agents include manganic acid, permanganic acid, orthophosphoric acid, metaphosphoric acid, hypophosphoric acid,
Carboxylic acids such as phosphorous acid, silicic acid, sulfuric acid, nitric acid and citric acid, sodium bicarbonate, ammonia water, water glass, silica sol, water reducing agents such as trade name Mighty 150, AE agents and superplasticizers, surfactants, foaming agents, Potassium stearate, sodium stearate, or a mixture thereof, which reacts with cement or a product thereof in the presence of water, and which is added and kneaded when water is added to cement to form raw mortar, It refers to an additive-type chemical added to a synthetic resin emulsion, and is particularly referred to as a reaction solution when the above-mentioned reactive agent is impregnated in a hardened hydraulic material. Unless otherwise specified, the reaction agents and reaction solutions used in the examples were water reducing agents, acids and / or alkalis added, and surfactants in appropriate amounts, but the present invention is not limited thereto. For example, strong acids are about 1 / 1,000,000 to 1 / 1,000,000 diluted solutions, carboxylic acids are about 1/200 to 1 / 500,000 diluted solutions or solutions, and alkalis are 1/100 to 1/20. About 10,000 diluents or lysates
Commercially available concrete admixtures can use a dilution liquid of about 3 to 1/100, and the amount used is 0.3 for cement.
Addition of about 100% is preferable. Curing in high humidity means sealed curing, moist air curing, steam curing by sending steam to a sealed chamber,
High-pressure curing or autoclave curing such as curing in high humidity in which evaporation of water is suppressed. The lime-based aqueous solution refers to calcium hydroxide obtained by adding water to a hydraulic substance, slaked lime, quick lime, or the like, or an aqueous solution mainly containing this.
Curing in air or curing in high humidity may be performed in an atmosphere of air or carbon dioxide. The water deficiency refers to water that is insufficient to allow a hydraulic substance to sufficiently hydrate, and may be water or hot water. Curing also includes semi-curing that hardens so that it does not collapse even if water or hot water is added.

As a conventional technique, Japanese Patent Laid-Open No. 57-27987 discloses high pressure steam curing / sealing curing /
It describes hot water curing, hot water curing after steam curing, and high pressure hot water curing. However, curing is only a technique for suppressing evaporation of water, not a technique for supplying insufficient water to a hardened hydraulic substance. The curing can be supplemented with hot water by hot water, but it is not cured in high humidity after supplementing with insufficient water, and calcium carbonate that reacts with carbon dioxide gas is dissolved and the white flower component that contributes to the strength elution, and When the hydraulic substance is removed after curing with warm water, the water evaporates rapidly and vigorously due to the difference from the ambient temperature, coarse coarse calcium carbonate is produced and becomes white sinter, and the evaporation pores are also large and the water absorption is large. Yes, there is little increase in strength thereafter.

Japanese Patent Publication No. 61-26516 discloses that a water-curable hydraulic inorganic shaped object is provided with an emulsion coating, and primary curing is performed under low temperature conditions of 30 ° C to 40 ° C, and secondary curing is performed under high temperature and high humidity conditions. A technique for curing is disclosed, and it is described that when secondary curing is performed under high temperature and high humidity conditions, the condensed water is absorbed by the shaped object and the water necessary for curing is replenished, but it is artificially insufficient. After replenishing water, or artificially and intermittently replenishing insufficient water, curing is not performed in a closed chamber in high humidity. The water repellency is due to the resin film, not the reaction product.
Further, there is no disclosure of a technique of performing wet air curing, steam curing, or coating a resin on the outside for hermetically curing after supplying insufficient water after demolding.

JP-A-62-3085 discloses that a water-repellent sheet hung on the inner surface of a curing cabinet is sprayed with water by a spray nozzle to form a water film, and steam is discharged to form a water film. Although a technique of curing with steam is disclosed, it is difficult to control the temperature and humidity with only steam, so it is a technique to control the temperature and humidity with a water film and steam, and apply water directly from a water spray nozzle to a hydraulic cement board. It does not replenish insufficient water.

Japanese Patent Publication No. 62-24374 discloses a technique of carbonating a shaped object of a hardened magnesia cement composition in a carbon dioxide gas atmosphere under heating and pressurization, but the present invention is not simply heated. , It's not about magnesia.

Furthermore, as a prior art, a technique is known in which a cement molded product is held in a mixed gas of water vapor and carbon dioxide and cured, but this is merely a curing method that suppresses evaporation of water, and artificially supplies insufficient water. It does not cure in high humidity while supplying or replenishing.

Combining the problems of the prior art, steam is a gas,
It is possible to suppress the evaporation of water, but it is not possible to replenish insufficient water unless it is liquid water. In conventional steam curing, steam from the boiler is sent to the curing chamber, and since the pressure in the curing chamber is large, it is not a closed chamber, but there is a gap etc. and it is breathable, and water is attracted by the rise of hot steam and water is generated. Evaporation, crystallization of cement gel and formation of coarse calcium carbonate do not increase late strength. When a high temperature hydraulic substance is taken out of the curing room and exposed to the outside air, the water evaporates rapidly, and the faster the evaporation rate of water, the larger the pores that become water-absorbent, and the more coarse the carbon dioxide in the mass. Calcium is generated and the surface becomes dirty.
Water evaporates even in a high humidity environment due to the difference between the temperature of the water-curing substance and the ambient temperature. If the evaporation of water of hydraulic material is zero or the evaporation of water is extremely slow due to curing in high humidity, it reacts with carbon dioxide in the air to form dense and fine calcium carbonate, which makes it difficult to absorb water. It was due to the fact that it did not notice that it had a strong property and increased strength, and that it was cured without considering the elution rate of calcium hydroxide and the evaporation temperature of water.

[Problems to be Solved by the Invention] An object of the present invention is to provide a method for curing a hydraulic substance that solves the problems of the above-mentioned conventional techniques.

[Means and Actions for Solving the Problems] (1) After artificially supplying insufficient water to the hardened hydraulic material after molding or demolding, the air or carbon dioxide gas atmosphere in the closed chamber , A method for curing hydraulic substances, which is characterized by performing curing in high humidity while suppressing evaporation of water.

Needless to say, the water-curing hydraulic substance that has been cured in the air is water-absorbing by curing, but even if it is cured in high humidity and water is not completely evaporated, Water is consumed and water absorbs in the harmonious reaction. In addition, underwater curing and autoclave curing are water curing by air curing before curing and are water absorbing. In the curing method of the present invention, the hardened water-absorbing hydraulic material is cured in high humidity in a closed chamber after supplementing insufficient water, so that there is no evaporation of water or the evaporation rate is extremely slow, and therefore evaporation Porosity is small, cement gel is generated during curing in high humidity, and dense and small calcium carbonate is also generated, the water gap is also small, and water absorption is made low enough to be mistaken for low water absorption or water repellency, and Strengthens. Supply of water shortage
You may replenish with hot water, a reaction liquid, or a lime-based aqueous solution. When replenishing the insufficient water to such an extent that water or hot water does not accumulate on the surface and the internal white flower component does not migrate to the surface, generation of white flower can be suppressed. It is preferable that the humidity in the closed chamber is 100%, but if the evaporation of water can be effectively suppressed, the degree of airtightness may be slightly incomplete. Can be replenished.

(2) In an air or carbon dioxide atmosphere in a closed chamber, the cured hydraulic substance is cured artificially and intermittently in a high humidity atmosphere while suppressing evaporation of water while supplementing insufficient water. A cure for hydraulic materials.

When insufficient water is replenished to the hydraulic substance in the closed chamber, high humidity occurs in the closed chamber at the same time as the insufficient water is supplied, the evaporation pores are reduced, the generation of cement gel proceeds, and the insufficient water is replenished. While it is stopped, dense and small calcium carbonate is generated, the water gap becomes small, the water absorption becomes low or the water absorption becomes difficult, and the strength becomes high.

(3) Curing of a hardened hydraulic substance is carried out in the air while artificially and intermittently supplying hot water having a temperature approximately the same as the temperature of the hydraulic substance, to cure the hydraulic substance. Law.

In the above curing, hot water having almost the same temperature as the temperature of the hydraulic substance is replenished as insufficient water, so it is difficult to evaporate water due to the temperature difference, and calcium carbonate is produced while the replenishment of hot water is stopped. However, it is economical because the gel formation is smooth and early strength can be obtained quickly by supplying insufficient water, and the hot water is economical because it is intermittently supplied, and when curing in a sealed room, minute and small calcium carbonate is also generated, and low water absorption To increase water resistance or water absorption and increase strength.

(4) A cured hydraulic material is impregnated with a reaction solution such as an aqueous solution of potassium stearate, and is cured in a high humidity atmosphere in which the evaporation of water is suppressed in an atmosphere of air or carbon dioxide. A cure for hydraulic materials.

The reaction liquid such as calcium hydroxide and potassium stearate reacts with each other to form a water-repellent reaction product such as calcium stearate, and in addition, the reaction product is trapped due to the formation of gel or dense calcium carbonate. And the poor water absorption continues.

(5) A method for curing a hydraulic substance, characterized in that the demolded hardened hydraulic substance is immersed in water to elute the white flower component and the adhering eluate is removed one or more times. .

When the hydraulic material after demolding is dipped in water, the white flower component elutes and adheres, but the adhered eluate can be easily removed while not carbonating, and not only the secondary white flower can be suppressed. ,
If water immersion and removal of adhering eluate are repeated, even water repellency will be exhibited, probably because the water gaps and evaporation holes are blocked with calcium carbonate.

(6) After molding a tubular material such as a fume tube, the synthetic resin emulsion is applied to the inner surface to form a film for curing, and after demolding to supplement the insufficient water, wet air curing, steam curing, or outside A method for curing a hydraulic material, which is characterized by applying a resin and then performing a hermetically-sealing cure.

Generally, steam curing is used for curing fume pipes, but it is a hollow material, so it takes up space, and high temperature steam curing does not increase long-term strength. However, the above-mentioned curing method does not require a curing chamber until demolding, and since curing is performed after replenishing insufficient water after demolding while suppressing evaporation of water, a large amount of cement gel is generated to increase strength and The resin film of can prevent deterioration due to sewage. When forming a resin film on the outer side (demolding surface), no curing chamber is required.

[Example] Portland cement was used as the cement in the following examples. In addition, wet air curing in the following examples, unless otherwise specified, put water at the bottom of the styrofoam curing box, put the test body on the cage child placed on it, so as not to get wet with water, and make the styrofoam. It was cured by closing the lid and sealing.

Example 1 (Claims 1 and 4) Cement: sand = 1: 3, W / C 55% (using water containing 1% of the amount of cement added to the water) of raw mortar was subjected to humid air curing for 24 hours, After the mold was removed, it was immersed in water for 1 hour and subjected to wet air curing for 23 hours, and further immersed in a 3% aqueous solution of potassium stearate for 1 hour and subjected to wet air curing for 23 hours, which was rendered water repellent. Water repellent was also obtained by using an aqueous solution of sodium stearate instead of potassium stearate. These are due to the formation of calcium stearate. Those using an aqueous solution of silicon also showed water repellency. Substitutes for microsilica and silica sol each exhibited poor water absorption. This is due to the formation of silicates. Wet-air curing is performed first, and the lacking water is replenished to perform further wet-air curing, so there is very little water evaporation, and cement gel and dense calcium carbonate are generated to make it difficult to absorb water and increase strength. Subsequent wet air curing after impregnation with the reaction solution can impart persistent water repellency, poor water absorption, etc., in combination with gel formation and dense ruthenium carbonate formation.

Example 2 (Claim 1) Cement: Sand = 1: 2 raw mortar was press-dehydrated and molded, and after air-drying for 2 days, it was dipped in water for 2 hours and then taken out. Bending strength was 147 kg / cm ^{2 after} being taken out for 8 days and taken out and air-cured for 4 days, and it was difficult to absorb water to some extent. As a comparative example, the air-cured one had a flexural strength on the same day of 123.2 kg / cm ² and was water absorbing.

Example 3 (Claims 1, 2 and 3) Immediately after molding, the foamed cement paste was steam-cured at 35 ° C, demolded after 6 hours, immersed in hot water at 40 ° C for 1 hour, and then autoclaved. The strength was 56 kg / cm ² and the specific gravity was 0.69.

Add water and aluminum powder to the appropriate amount of cement, slaked lime and silica sand fine powder to foam it, and subject it to wet air curing for 6 hours and 30 minutes at 35 ° C.
The one that was soaked in hot water, sprayed with hot water again every 30 minutes, and subjected to wet air curing for 6 hours, and then autoclaved,
It was less water absorbent than ALC.

Example 4 (Claims 1 and 2) Cement: sand = 1: 3, W / C 50% raw mortar was molded and cured in a moist air for 4 days (after demolding, immersed in water for 1 hour for 1 hour) ), The 10-day compressive strength of that which was then air-cured was 234.
It had a low water absorption of 04 kg / cm ² and a specific gravity of 2.00. As a comparative example, the same-day compressive strength of air-dried curing was 163.74 kg / c.
It had m ² and a specific gravity of 1.88 and was water absorbent.

Example 5 (Claims 1, 2 and 3) Cement: sand = 1: 3, W / C 55% (using water added with 1% of the amount of cement as water) of raw mortar, in a heat-insulating closed chamber After 6 hours, 35 ° C. hot water was sprayed at 30 minute intervals for curing for 18 hours, and the 7-day compressive strength of the mortar which had been subjected to the same hot water curing curing for 24 hours after demolding was 270 kg / cm ² .

Example 6 (Claims 1, 2, 5) 100 parts of cement, 10 parts of red shell, and 38 parts of water containing 1% of a reaction agent were kneaded and molded into a plate shape on a plastic plate, and immediately after molding at 35 ° C. Those that had been steam-cured for 16 hours produced a glossy surface. Immediately after demolding, the product that had been soaked in water for 24 hours and picked up had the eluate attached to the surface, but it can be easily wiped off.
When water immersion, removal of eluate and drying were repeated, the color gradually became dark and even water repellency was exhibited. It should be noted that both the one that was subjected to the steam curing for 6 hours and the one that was air-dried at 30 ° C after molding had gloss on the bottom surface, and after removing the mold, supplement the insufficient water, or replenish the insufficient water while supplementing the insufficient water as necessary. Air curing was performed to obtain a cured product with low shrinkage and high strength. The same applies to the case where the above-mentioned kneaded product is laminated on an uncured hydraulic material as a paint.

Example 7 (Claim 6) After molding a tubular material such as a fume tube, a synthetic resin emulsion is applied to the inner surface to form a film for curing, and after demolding, water is replenished to replenish the moisture, air, and steam. Curing was performed, or resin was applied to the outside for hermetic curing.

[Effects of the Invention] The present invention is configured as described above and is effective in increasing the strength of a hydraulic material, reducing water absorption, making it difficult to absorb water, making it water repellent, and suppressing white sinter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (31) Priority claim number Japanese Patent Application No. 1-172921 (32) Priority date Hei 1 (1989) July 6 (33) Priority claiming country Japan (JP) (31) Priority Claim number Japanese patent application No. 1-179118 (32) Priority date No. 1 (1989) July 13 (33) Country of priority claim Japan (JP) (31) No. of priority claim Japanese patent application No. 1-198005 (32) Priority Hihei 1 (1989) August 1 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 1-239863 (32) Priority Day Hei 1 (1989) September 18 (33) ) Priority claiming country Japan (JP) (31) Priority claiming number Japanese Patent Application No. 1-269095 (32) Priority date Hei 1 (1989) October 18 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application No. 1-283112 (32) Priority Day No. 1 (1989) November 1 (33) Country of priority claim Japan (JP) (31) Priority claim number Japanese Patent Application No. 1-292447 (32) ) The other day Hei 1 (1989) November 13 (33) Priority claiming country Japan (JP) (31) Priority claim number Japanese Patent Application 2-6407 (32) Priority Day Hei 2 (1990) January 17 (33) (72) Japan (JP) (72) Inventor Hiroshi Mitsuo 1-28-7 Miyasaka, Setagaya-ku, Tokyo Maison Wada 402 Examiner Hideo Tokunaga (56) Reference JP-A-57-27987 (JP, 27987) A) JP 62-3085 (JP, A) JP 62-55174 (JP, A) Actual development 57-138947 (JP, U) JP 61-26516 (JP, B2) JP 62 -24374 (JP, B2)

Claims (6)

(57) [Claims] 1. High humidity that suppresses evaporation of water in an air or carbon dioxide atmosphere in a closed chamber after artificially supplying insufficient water to a hardened hydraulic material after molding or demolding. A method for curing hydraulic substances, which is characterized by medium curing. 2. Curing in a high humidity atmosphere in which a hardened hydraulic material is artificially and intermittently replenished with deficient water while suppressing evaporation of water under an atmosphere of air or carbon dioxide gas in a closed chamber. A characteristic curing method for hydraulic materials. 3. A hydraulic material characterized by subjecting a hardened hydraulic material to air curing while artificially and intermittently supplying hot water having a temperature substantially the same as the temperature of the hydraulic material. Regimen. 4. A cured hydraulic material is impregnated with a reaction solution such as an aqueous solution of potassium stearate, and is cured in a high humidity atmosphere while suppressing evaporation of water in an atmosphere of air or carbon dioxide. A cure for hydraulic materials. 5. A demolded hardened hydraulic material is immersed in water to elute the white sinter component and the adhered eluate is removed one or more times. Regimen. 6. After molding a tubular material such as a fume tube, a synthetic resin emulsion is applied to the inner surface to form a film for curing, and after demolding to supply insufficient water, wet air curing, steam curing, or A method of curing a hydraulic material, which is characterized by applying a resin to the outside to perform a hermetic curing.