JPH10194801A - Concrete repairing liquid-encapsulated aggregate, and concrete blended with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a concrete having a crack self-repairing function and to obtain an aggregate to be blended into the concrete. SOLUTION: This aggregate 1 is obtained by impregnating an aggregate main body 2 consisting of a porous material with a repairing liquid 3 for plugging the crack by releasing to the crack generated in the concrete to encapsulate the repairing liquid 3. The outside surface is preferably covered with a coating film 4. The concrete blended with the aggregate is constituted so as to repair the crack naturally with oneself by releasing the repairing liquid from the aggregate when the crack is caused.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aggregate to be incorporated in concrete for repairing cracks generated in concrete, and to concrete having a self-repairing function for cracks when it is incorporated.

[0002]

2. Description of the Related Art As is well known, concrete itself is a material which is brittle and easily cracks. Therefore, various measures for preventing cracks have been proposed and practically used.
It is extremely difficult to completely prevent concrete cracks. For this reason, especially when it is necessary to prevent the occurrence of cracks, for example, concrete applied to structural members that need to secure sufficient strength or walls that require a high degree of waterproofness, cracks Check frequently for
When a crack is found, it must be repaired promptly.

[0003]

However, frequent inspections and repairs of concrete require a great deal of labor and cost, and repairs are impossible even if inspection is impossible or cracks are found. In many cases, it is difficult to detect cracks until they have grown to a certain extent, so it is difficult to detect cracks early.Therefore, effective improvement measures are needed .

Japanese Patent Laid-Open Publication No. Hei 3-215334 discloses an aggregate to be mixed with concrete for the purpose of finding cracks and repairing the same. In this method, a chemical solution that cures by reacting with concrete components or water or air is encapsulated in a capsule made of a brittle material such as water glass,
Further, the outside is protected by a hardened cement body shell. This aggregate is to be destroyed at the same time as the concrete containing it cracks, and the chemical solution in the capsule penetrates into the crack and hardens, so that the concrete containing it has a crack self-repair function. It is said that it can be.

[0005] However, the above-mentioned aggregates cannot be effective for the following reasons, and have not been widely used. That is, since the above-mentioned aggregate has a configuration in which a chemical solution is enclosed in a capsule that is easily broken such as water glass, when mixing and kneading it with fresh concrete, When cast, it is easily broken by contact with a mixer, concrete pump, or other coarse aggregate or reinforcing steel. It is not always easy to mix concrete and harden concrete as it is.
Moreover, even if the above-mentioned aggregate is blended into the concrete while maintaining soundness, voids will be formed in the aggregate after the concrete is cracked, the capsule is destroyed and the chemical solution inside is released. Therefore, the essential function of the aggregate is lost, and the strength of the concrete is reduced.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a concrete having a function of being able to repair itself by itself when a crack occurs, and an effective method capable of realizing such concrete. To provide a suitable aggregate.

[0007]

SUMMARY OF THE INVENTION In view of the above circumstances, the aggregate according to claim 1 is used for repairing cracks generated in concrete by being used by being mixed with concrete, and is intended to be used for porous materials. The present invention is characterized in that an aggregate body made of a material is impregnated with a concrete repairing liquid that is released into a crack generated in concrete and closes the crack, thereby being enclosed.

[0008] In the aggregate according to the second aspect of the present invention, the outer surface of the aggregate is coated with a coating film so that the repair liquid is included in the aggregate main body by the coating film, and the aggregate is coated on the concrete. When a crack occurs, the coating film is broken and the repair liquid is released.

[0009] The concrete according to claim 3 further comprises:
The above-mentioned aggregate is compounded, and when the crack is generated, the repair liquid is released from the aggregate for the crack so that the crack can be repaired by itself. Is what you do.

[0010]

Embodiments of the present invention will be described below. FIG. 1 is a schematic diagram showing one embodiment of a concrete repair liquid-containing aggregate (hereinafter simply referred to as aggregate) 1 according to the present invention, and FIG. 2 is a schematic diagram showing one embodiment of a concrete 5 according to the present invention. The concrete 5 contains the above-mentioned aggregate 1 shown in FIG.

The above-mentioned aggregate 1 is able to close the crack C by being released into the many holes 2a in the aggregate body 2 made of a porous material and into the crack C generated in the concrete 5. The repair liquid 3 is impregnated and included, and the outer surface thereof is covered with a coating film 4.

The above-mentioned aggregate main body 2 is not particularly limited as long as it is porous and has a large number of pores 2a and can function as an aggregate. For example, volcanic debris, barley stone, molecular sieve Natural aggregates or artificial lightweight aggregates that have been widely used in the past, such as porous glass and porous silica, can be suitably used. The size of the above-mentioned aggregate main body 2 may be equivalent to that of a normal aggregate, and may have an appropriate particle size distribution if necessary.

The above-mentioned repair liquid 3 is usually liquid and has a property of being hardened by reacting with water, alkali components or air in the concrete upon contact with the concrete, or cracking by the reaction. C, a reaction product capable of filling C, for example, an alkali silicate chemical known as a surface strengthening agent for concrete (for example, an alkali silicate aqueous solution such as a crystal sealer manufactured by Nikko Co., Ltd. Ultra-ash (trade name) or an epoxy resin that cures by reacting with an alkali component of concrete can be used. In any case, the repairing liquid 3 can maintain a liquid state for a long period of time while being contained in the pores 2a of the aggregate main body 2, and the crack C is generated in the concrete to cause the aggregate main body 2. When the crack 2 is destroyed or the coating film 4 is destroyed, it is naturally released from the aggregate body 2 and flows out into the crack C, or when the crack C is minute, the crack C is formed by capillary action.
And has a function of hardening or reacting naturally in the crack C and closing the crack C with the product.

It is preferable that the repair liquid 3 has a low reactivity with the concrete 5. If the reactivity is too high, the repair liquid 3 released from the aggregate 1 may not sufficiently cover the entirety of the crack C, and the reaction may proceed so that the entire crack C may not be sufficiently closed. Therefore, it is preferable that the reaction proceeds after the repair liquid 3 has sufficiently spread within the crack C while taking into account the viscosity and fluidity of the repair liquid 3. However, before the concrete 5 hardens, it is preferable that the reactivity between the repair liquid 3 and the concrete 5 before hardening is high. In this case, even if the aggregate 1 and the coating film 4 are broken during the kneading or casting and the repair liquid 3 is released, the released repair liquid 3 and the concrete 5 before hardening are promptly mixed. In order to prevent further release. In this regard, most preferably, the repair liquid 3 has such a property that the reactivity with the concrete 5 is high until the concrete 5 is hardened, and the reactivity decreases after the concrete 5 is hardened.

On the other hand, the above-mentioned coating film 4 encloses the repair liquid 3 in the pores 2a of the aggregate main body 1, and when the crack 5 is formed in the concrete 5, it is destroyed together with the crack C and the repair liquid 3 is removed. The coating film 4 is formed of, for example, water glass, hardened cement, paraffin wax, polyolefin resin, epoxy resin, aminoplast resin, polyamide resin, urethane resin, acrylic resin, unsaturated polyester resin, and the like. And the like can be suitably adopted.

In order to manufacture the aggregate 1 as described above, the repair liquid 3 is impregnated into the aggregate main body 2 by an appropriate method, for example, a vacuum impregnation method, and a coating film 4 is formed on the surface thereof by an appropriate method. Just do it.

The coating film 4 is coated with the above-mentioned repair liquid 3
May be formed. That is, for example, when the repair liquid 3 is cured by reacting with water, water is sprayed on the surface of the aggregate body 2 immediately after the repair liquid 3 is impregnated, or the aggregate body 2 is immersed in water. By immersing, the repair liquid 3 adhering to the surface of the aggregate body 2 is reacted with water and hardened to form a coating film 4.
It can be. However, at this time, only the repair liquid 3 adhering to the surface of the aggregate body 2 reacts to form the coating film 4, and the repair liquid 3 contained in the holes 2a.
It is necessary to control the reaction so that the reaction does not progress until that time, or to use the repair liquid 3 having such properties.

Alternatively, the aggregate body 2 immediately after being impregnated with the repair liquid 3 is directly blended and kneaded in fresh concrete, and the repair liquid 3 adhering to the surface of the aggregate body 2 is removed from the water in the fresh concrete. It is also possible to react with an alkali to form the coating film 4. In other words, the coating film 4 is formed when the aggregate body 2 that has only been impregnated with the repair liquid 3 and does not form the coating film 4 and is mixed with fresh concrete is formed. The concrete 5 containing the aggregate 1 formed with 4 is hardened as it is. Also in this case, only the repair liquid 3 attached to the surface of the aggregate main body 2 reacts at the time of kneading to form the coating film 4, and the pores 2 a of the aggregate main body 2 are formed.
It is necessary to control the reaction so that the reaction does not progress to the repair liquid 3 contained therein, or to make the repair liquid 3 have such properties. In this point, as described above, the reactivity with the concrete 5 is high before the concrete 5 is hardened (therefore, the coating film 4 is quickly formed during the kneading, and the reaction does not reach the repair liquid 3 in the pores 2a). Repair liquid 3 which has a property of decreasing after hardening of concrete 5 (thereby, the repair liquid 3 released due to crack generation reacts after spreading sufficiently in the crack).
It is most preferable to use

In order to produce concrete 5 containing the aggregate 1 produced as described above, an appropriate amount of the above-mentioned aggregate 1 is mixed with fresh concrete, and fine aggregate and other ordinary Aggregate is also compounded together and kneaded in the same manner as ordinary concrete to disperse the aggregate 1 evenly in the concrete 5 and only to be poured into the formwork as in the ordinary case. By appropriately adjusting the size of the aggregate 1, the amount of the repair liquid 3 impregnated into the aggregate 1, and the amount of the aggregate 1 mixed with the concrete 5, the amount of the repair liquid 3 mixed into the concrete 5 and its distribution Can be adjusted so as to be optimal. Therefore, for example, when a large crack is expected to occur, it may be adjusted so that a large amount of the repair liquid 3 is mixed into the concrete 5.

The concrete 5 thus manufactured
When a crack C is formed on the aggregate 1, the crack C normally extends so as to sew the aggregate 1, and as shown in FIG.
With the occurrence, the aggregate 1 is also destroyed, or only the coating film 4 is destroyed or peeled off from the aggregate main body 2, and the repair liquid 3 contained in the aggregate main body 2 is released and flows out into the crack C, Alternatively, when the crack C is fine, the crack C oozes out due to the capillary action, and the repair liquid 3
Inside the concrete or reacts with the moisture or alkali components in the concrete, and the crack C is naturally closed by the reaction product. That is, the concrete 5 has a self-repair function for cracks, and can prevent a decrease in strength and a decrease in water stopping performance due to the occurrence of cracks. In addition, the strength and water stopping performance temporarily decrease due to cracks. Even if the crack is repaired naturally, the strength and the water stopping performance can be quickly restored.

Therefore, such concrete 5
For example, if it is applied as a structural member that needs to secure sufficient strength or as a waterproof wall that requires a high degree of water stopping performance, the required structural strength and reliability of the water stopping performance are naturally secured for a long time In addition, the inspection work for confirming the presence or absence of crack generation and the work for repairing the crack found by the work, which are conventionally required, are unnecessary, which is extremely effective.

Of course, in the above-mentioned aggregate 1, the aggregate main body 2 functions as a normal aggregate, and the aggregate 1 is not easily broken at the time of being kneaded or poured into the concrete 5. Therefore, the aggregate 1 can be blended into the concrete 5 while keeping the sound, and even if the aggregate 1 is destroyed due to the crack generation, no void is generated. The original function as a material can be maintained as it is, and the strength of concrete is not impaired. In this respect, the repair liquid 3 is much more effective than the case where the repair liquid 3 is simply encapsulated in a fragile capsule and blended into the concrete 5.

Examples of the aggregate of the present invention and concrete containing the same will be described below. Manufacture of Aggregate Spherical porous silica (eg, Godball D-11C manufactured by Suzuki Yushi Kogyo Co., Ltd.) as an aggregate body, and an alkali silicate agent (eg, Nikko Corporation, which is an alkali silicate aqueous solution) as a repairing liquid Paraffin wax was used as a material for the coating film. The god ball was immersed and impregnated in a stock solution of crystal sealer, and then dried at room temperature for 7 days until the surface became sticky. This was dispersed in paraffin wax melted at 90 ° C., and then spray-cooled with a spray cooler to form a paraffin wax coating film. Manufacture of concrete A concrete specimen having the following composition was manufactured using the aggregate manufactured as described above. The size of the specimen is 40mm x 40mm
× 100 mm. Normal Portland cement 100 parts Water 50 parts Silica sand 70 parts Above-mentioned repair liquid inclusion aggregate 50 parts Crack generation After the specimen is cured for one month and dried, 3-4 fine cracks are applied by applying bending force. A spot was formed, water was applied to the surface, and the surface was further left for one month. As a comparative example, a specimen that had been cured for two months without causing cracks was also prepared. Observation Results The specimen was again broken by applying a bending force, and the surface of the crack was observed. As a result, the crack was filled with the glassy substance generated by the repair liquid released from the aggregate. The aggregate that released the repair fluid was destroyed, but no voids were formed. The flexural strength of the specimen that was repaired by generating a crack was 1.2 times higher than that of the comparative example in which no crack was generated.

The embodiments of the present invention have been described above. However, the present invention is not limited to the above, and can be appropriately designed and variously modified. For example, as the material of the aggregate body 2, the repair liquid 3, and the coating film 4, other than those exemplified above can be naturally used as long as they have similar properties and functions.

The concrete 5 of the present invention is particularly suitable for application to a structural member or a water stop wall which needs to prevent the occurrence of cracks as described above, but its use is particularly limited. Instead, walls, columns, beams, panel zones that are their joints, roof slabs, floor slabs, outer walls, underground outer walls, driven formwork, piles, foundations, earthquake-resistant walls, and so on, in general buildings and structures It can be widely used as an underground wall. Examples of applications of a structure that is preferably constructed using the concrete 5 of the present invention include a water storage tank, a waste storage facility, a radiation shielding wall, a reactor containment vessel, and a floor slab of a road bridge. Can be

Further, it is of course possible to construct the concrete 5 of the present invention by cast-in-place. However, if the concrete 5 of the present invention is manufactured as a precast product in which the aggregate 1 of the present invention is included, a large amount of concrete can be obtained. Production is possible and quality control is easier.

If the repair liquid 3 is colored so that it is released from the aggregate 1 and the crack is repaired, it can be easily confirmed that the crack is repaired. Can be easily confirmed visually.

[0028]

As described above, the aggregate of the present invention is obtained by impregnating an aggregate body made of a porous material with a repair liquid which is released into cracks formed in concrete and closes the cracks. At least, if necessary, the outer surface is covered with a coating film, so when this is only mixed with concrete, when the concrete cracks, the repair liquid is released from the aggregate at the place where the crack occurs. The cracks can be closed by themselves, and they have the essential function of aggregate and are not easily destroyed during concrete production. It does not impair the function and thus can be used to achieve an effective concrete with a self-repairing function for cracks. In addition, the concrete of the present invention has a function of self-repair of a crack by being mixed with the above-mentioned aggregate, and therefore, it is not necessary to perform an inspection work for checking whether or not a crack has occurred or a repair work for the crack. Therefore, it is particularly suitable when applied to, for example, a structural member that needs to ensure sufficient strength, a wall that requires a high degree of waterproofness, and the like.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of the aggregate of the present invention.

FIG. 2 is a schematic view showing concrete containing the same aggregate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aggregate 2 Aggregate main body 2a Void 3 Repair liquid 4 Coating film 5 Concrete C Crack

 ──────────────────────────────────────────────────続 き Continued on the front page (71) Applicant 000208570 Yoshihiko Ohama 2-14-10-402 Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture (71) Applicant 596147312 Katsunori Demura 2-2-1 Omachi, Koriyama-shi, Fukushima Prefecture ( 71) Applicant 597000858 Tatsuya Numao 6-9-22-404, Ayukawa-cho, Hitachi City, Ibaraki Pref. (71) Applicant 000002299 Shimizu Corporation 1-3-2 Shibaura, Minato-ku, Tokyo (71) Applicant 000132404 Three Bond Co., Ltd. 1456 Address, Hazama-cho, Hachioji-shi, Tokyo (71) Applicant 592082206 Three Bond Unicom Co., Ltd. Person Nomura Noriaki 4-5-11 Minami Yagiyama Minami, Sendai City, Miyagi Prefecture (72) Inventor Koji Otsuka 4-2-282 Takamori, Izumi Ward, Sendai City, Miyagi Prefecture (72) Inventor Yoshihiko Hama 2-1-10-402 Hiyoshi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture (72) Inventor Katsunori Demura 2-2-1-401, Omachi, Koriyama-shi, Fukushima Prefecture (72) Inventor Tatsuya Numao 6, Ayukawacho, Hitachi-shi, Ibaraki -9-22-404 (72) Inventor Yoshio Kaneko 1-3-2 Shibaura, Minato-ku, Tokyo Shimizu Corporation (72) Inventor Yukio Sato 67, Kanda Sakuma Kishi, Chiyoda-ku, Tokyo Three Bond Unicom Co., Ltd. (72) Inventor Hanada Minami 1456 Zamacho, Hachioji-shi, Tokyo Three Bond Co., Ltd.

Claims (3)

[Claims] 1. An aggregate for repairing a crack generated in concrete by being used by being mixed with concrete, wherein the aggregate is released into the aggregate formed of a porous material into the crack formed in concrete and is released into the aggregate. An aggregate containing concrete repair liquid, wherein the aggregate is impregnated with a concrete repair liquid that closes a crack. 2. A concrete repair liquid-containing aggregate according to claim 1, wherein an outer surface of the aggregate is covered with a coating film so that the repair liquid is included in the aggregate body by the coating film. Characterized in that, when a crack is generated in the concrete, the coating film is broken and the repair liquid is released, whereby the concrete repair liquid-containing aggregate is characterized in that the repair liquid is released. 3. The concrete repair liquid-containing aggregate according to claim 1 or 2, wherein when the crack is generated, the repair liquid is released from the aggregate with respect to the crack, whereby the crack is released. Concrete characterized by being able to repair itself by itself.