JPS5876656A - Repairing of cement structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a method of repairing existing cement mortar structures, cement concrete structures, etc., particularly for outdoor cement structures, in order to improve their durability in terms of waterproofness. or regarding repair methods.

Conventionally, as a method for repairing damaged parts of a &
Attempts have been made to strongly adhere the cement composition to the structure by applying a cement composition consisting of water, cement and aggregate after applying 1Jt.

However, in this case, apply the adhesive and then cement)
The optimum leaving time before applying JIIE4&+ varies greatly depending on the environmental temperature, the presence or absence of personnel, strength, etc., so there was a drawback that it was necessary to set and adhere to this optimum time at the site. . In other words, if the above-mentioned standing time is too short, the adhesive will not be sufficiently cured and its viscosity will be low, causing the cement composition to slip and fail to achieve its intended purpose. Since the cement layer is completely cured, the applied cement composition will separate from the MK side and be removed. Therefore, the air resistance of cement structures repaired by this method varied greatly.

In recent years, a cement composition containing water, cement, polyester for cement, and if necessary aggregate has been used as a cement composition. Point 4: Although it is known that the parent compound cannot be used with an epoxy adhesive or the like (although it has an initial adhesion strength of 1 or more against existing cement structures),
Many examples were sold because the R layer that had been repaired over time was separated from the underlying existing cement structure.

In view of the above-mentioned conventional oil repair method, the present invention eliminates the need to use epoxy - The purpose is to provide a method for repairing 11 cements, and its gist is that when repairing an existing cement structure using a poly-cement composition, the structure should be repaired. 1111rKl
The molar ratio of aluminum chloride to silicon dioxide is 1:l-1
: Repair of cement 11, characterized by applying fluoro-crystalline aluminum citrate of 10 to make the boundary between the cement structure in the repaired area and the polymer cement layer provided by the repair impermeable. It lies in the method.

The polymer cement composition used in the present invention includes ice, cement, a polymer for cement, and, if necessary, aggregate. Conventionally known compositions are widely used, and depending on the presence or absence of aggregate, type, etc., polymer cement paste, It is called polymer cement mortar, polymer cement concrete, etc. As the cement, Portland cement, alumina cement, mixed cement, etc. are often used, and these can be used alone or in an appropriate mixture.

1 Polymers for cement exist as polymers in cured polymer cements and are tempered for the purpose of improving their impact resistance, adhesion to private house structures, etc. Specific examples include natural rubber, rubber, etc. aCt pre rubber, butadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, methyl methacrylate ptashi Z > = f
Synthetic rubber such as rubber, polyvinyl acetate, ethylene! Thermosetting resins such as polyacrylic acid ester, polyvinyl chloride, polyvinylidene chloride, polyglopionate vinyl A/I*, thermosetting resins such as IIIWiI and epoxy resins are listed. These are synthesized using natural rubber and epoxy resin, often by emulsion polymerization, and then appropriate stabilizers, antifoaming agents, etc. are added, and they are usually synthesized using emulsion or latex.
It is used in Water-soluble polymers such as polyvinyl alcohol, polyacrylate, polyethylene oxide, methylcellulose, and hydroxyethylcetate A-lose can also be used as workability improvers. Among the above-mentioned polymers, from the viewpoint of adhesion to existing cement structures, flexibility, impact strength, bulkiness, etc., ethylene-butadiene rubber, acrylonitrile-butadiene rubber, ethylene-vinyl acetate copolymer, and the like are particularly preferred. These polymers are usually added in the form of 10 to 30 parts by weight S per 100 parts by weight of cement.

The type and wrinkles of the aggregate to be used as necessary are determined depending on the extent and scale of the damage to the existing structure to be repaired, the manner of repair described below, etc., but as fine aggregate, Silicic acid whose main component is silicic anhydride with a particle size of 15% or less is preferably used, and is usually used from the viewpoints of workability, shrinkage properties during curing of the polymer cement composition, various strengths after curing, and economic efficiency. 400 parts by weight or less for 190 parts by weight of cement), and as the coarse aggregate, conventionally known chestnut stone or crushed stone for cement concrete is used.

The aluminum silicate used in the present invention has a molar ratio of aluminum oxide to silicon dioxide of 1:1 to 1:1G.
It is also amorphous and its hydrate may be used.Amorphous aluminum silicate is made of aluminum silicate. Rarena- also means Of, which means that for monochrome Xmt-horizontal axis t
When we take an X-ray powder 1-fold spectrum of Kamishi aluminum silicate with the a-fold angle and the intensity of the diffraction line as the vertical axis, it is certain that a crystal lattice exists at a length that gives a gentle mountain shape. This is determined from the fact that the resulting unique peak does not appear.

The above-mentioned amorphous aluminum silicate can be obtained, for example, by combining aluminum sulfate and a hindlimb aqueous solution of a sodium silicate tube dissolved in an appropriate amount of water, and reacting the two in the reaction solution while adjusting the pH, temperature, etc. It will be done. Reaction conditions such as temperature
By adjusting the f-coupling, an appropriate molar ratio of aluminum oxide and silicon dioxide can be synthesized. Considering that the solubility in alkaline water is poor, silicon dioxide in aluminum silicate is high, that is, the above molar ratio is small.
At is preferred, but considering the ease of production, it is also preferred that the eel has a molar ratio of aluminum oxide to silicon dioxide θ of approximately 1:9.

On the other hand, ε amorphous aluminum silicate also exists as a hydrate in the clay minerals of the Volcanic Sawa layer, and is collectively called allophane, including cases containing a small amount of crystalline part. There have been no reports of the existence of a crystal lattice.

The molar ratio of aluminum oxide and silicon dioxide in allophane is 1:1 to 1:2, but when comparing the above synthetic amorphous aluminum silicate with the same molar ratio and allophane, the cause is not clear, but the present invention In this case, synthetic amorphous aluminum silicate (E) is usually used, but natural amorphous aluminum silicate may be used in some cases. The moles of aluminum diam and silicon dioxide are used depending on the weather and environmental conditions at the repair site, whether they are synthetic or natural, etc., but usually, the moles of aluminum diam and silicon dioxide are determined based on the climatic and environmental conditions at the repair site, and whether it is a synthetic or natural product. a5-10
Parts by weight are preferably 1 to 5 parts by weight.

In addition, these amorphous aluminum silicates have the property of decomposing alkaline PH to the extent that occurs in cement compositions containing water and cement, so in the present invention, they are usually mixed into polymer cement. In some cases, alkaline aqueous solution I [with a pH of about ε above] is used as
It is used by dissolving K.

Hereinafter, the method of repairing cement 11 by the method of the present invention will be explained.

First, 100 parts by weight of the above-mentioned amorphous aluminum silicate, 0 to 400 parts by weight of the aggregate, and an appropriate amount of the above amorphous aluminum silicate are combined.
Use material A. If the damaged part of the 7-year-old item is more than 20% deep, use sand O, chestnut stone, or crushed stone as aggregate.
It is preferable that the comb material contains alkali-resistant glass fiber.Next, the polymer ctex (material 1) is mixed uniformly with water and the tA material as necessary. The resulting polymer cement composition may be applied directly to the repaired area of an existing cement structure using a plastering trowel or sprayed with a mortar gun, similar to the conventional cement mortar application method. In this case, construction is possible even if the existing structure that comes into contact with the polymer cement composition is wet. The above polymer cement composition may be obtained by mixing the raw materials by a procedure other than the above.

In addition, especially when a sufficient thickness of the polymer cement layer provided by repair is required, the above aluminum silicate t
It is also preferable to pre-apply a primer containing a cement polymer and, if necessary, cement and aggregate to the area to be repaired, and then coat that area with the above-mentioned polymer cement composition that does not contain aluminum silicate. It is.

Furthermore, as another possible repair uniformity, after coating the area to be repaired with a polymer cement composition that does not contain the above-mentioned Keishun aluminum, a suitable alkaline aqueous solution in which the above-mentioned aluminum silicate is dissolved is applied to the coating layer. Examples of methods include coating and impregnating.

Since the amorphous aluminum silicate dissolves in alkaline aqueous solution Km in the Fil@ range, for example, when it is mixed into a polymer cement composition and applied to an existing cement structure, the alkali content in the composition and the existing structure are mixed. Capillary-like ' in the polymer cement hardened by hydration reaction while alkaline leached from the surface forming! 1FtK also penetrates and forms similar insoluble crystals, and in combination with the presence of the cement reamer, the boundary area between the cement structure at the repair site and the polymer cement layer provided by the repair becomes It is assumed that the material will be made water-impermeable.

The method for repairing a cement structure of the present invention is configured as described above, and amorphous aluminum silicate with a molar ratio of aluminum oxide to silicon dioxide of 1:1 (N1:10) is applied to the portion of the cement structure to be repaired. As a result, the boundary between the cement structure in the repaired area and the polymer cement-t provided by the repair is made impermeable, so according to the present invention, even if rainwater seeps into the interior of the existing cement structure, it will not be as bad as before. The polymer cement composition does not reach the interface with the polymer cement layer and stay there, and is not subject to the peeling effect of water staying at the interface, which combines with the good adhesion of the polymer cement composition to existing cement structures. The polymer cement layer provided by the repair will not peel off or fall off over a long period of time.

Since the method of the present invention does not require the use of two-component curing epoxy or adhesive cutting, there is no need to manage the optimum standing time after application, and therefore, according to the present invention, a polymer cement with uniform durability can be obtained. A layer is formed.

Next, examples of the method of the present invention will be shown.

Example 1 Sugatoshi Portland cement 1 () 0 parts by weight, Kui sand 20
0 parts by weight, synthetic amorphous aluminum silicate (most ratio of aluminum oxide to silicon dioxide, 1:9) 1
5 parts by weight of styrene-butadiene rubber latex (hereinafter referred to as SBR latex) and 40 parts by weight of styrene-butadiene rubber latex (rubber particle size: 18 parts by weight) and water (22 parts by weight and 11 parts by weight) were further mixed with 32 parts by weight of water to form a polymer. The obtained cement composition was washed with water on a cement-concrete floor board that had been constructed for about 3 years, and the polymer cement composition was applied to the floor 1 [K] in a 2 m long gap with a trowel. The surface was smooth and the coating IIVtIR with a thickness of 10% was cured by air-drying at room temperature.

For the specimen prepared in the same manner as above, the entire WA of the polymer cement layer was repaired using a trailing edge water device 3 days after construction.
It covers an area of approximately S-60 minutes during the day and 60 minutes at night.
Water was sprinkled every day for minutes. The amount of water sprinkled is 1O0l for 1-
/ I made it so that it was four o'clock.

Under these conditions, the peeling status of the newly provided polymer cement layer was measured over time. The measurement method is based on the hammer test, that is, if the surface of the polymer cement layer is struck with a hammer, if the cement layer lifts, it can be detected as an alternation, which indicates the occurrence of peeling of the cement layer. can be recognized.

The results were as per the second barley.

Sosei Yuu~6 A specimen was prepared in exactly the same manner as in Example 1, except that the type and amount of synthetic amorphous aluminum silicate and the type of polymer latex were changed as shown in Table t-111. A similar test was conducted. The results were as shown in Table 2 of #'i.

(hereinafter referred to as Reihaku) 11Il Table - All parts except for the thickness of the coating layer are expressed in parts by weight.

・Indicates the molar ratio of aluminum oxide to guyrin dioxide in aluminum silicate.

shows.

2-L Judgment method Actual V% ~ ~ 1 An x 2 m wide polymer cement layer T - Divide into 20 cm x 20 cm squares and hit each section with a hammer to ensure that even one section does not produce cavity sound. A score of 1 was scored as ×, and a score of 1 kO was scored when no hollow sound was heard throughout the entire section.

Comparative Example 14 was carried out in exactly the same manner as in Example 1 except that amorphous aluminum silicate was added to the polymer cement composition.
Sample 1*jilEL was subjected to the O test in the same manner as in Example 1.

The results were as follows.

patent applicant Sekisui Chemical! Kinsha Co., Ltd. Representative: Haruti Fujinuma Nirehon Chemical Industry Co., Ltd. Representative - Kunio Yanagi

Claims (1)

[Claims] 1. When repairing an existing cement structure using a polymer cement composition, the number f of the structure to be repaired is
The molar ratio of frK aluminum fluoride to silicon dioxide is 1:
1 Amorphous aluminum of #1:10 is applied to make the boundary S between the cement structure in the repaired area and the poly-cement layer provided by the repair impermeable. How to repair 11 things in seven men. 111! A method for repairing item I11E where the ratio of aluminum oxide to silicon dioxide in crystalline aluminum silicate is approximately 1:9. Since the polymer cement composition contains water, cement, sand, and I limmer for cement, Section II 1 xaSS Section 11O
Repair method. 4. The repair method according to any one of paragraphs 1 to 3, in which 0.5 parts by weight or more of amorphous aluminum silicate t-cement and sand are used in a total amount of 100 parts by weight.