JP4403155B2 - Concrete water channel repair method - Google Patents

Description

  The present invention relates to a concrete water channel repair method, and in particular, when repairing a bottom plate or a side plate of a water channel made of a concrete structure, it has excellent adhesion durability, excellent workability, and particularly excellent wear resistance. The present invention relates to a waterway repair method that can provide a repair surface.

In waterway structures made of concrete structures, surface wear due to the influence of water flow, wear and chipping due to mixed gravel and sand, etc. occur due to long-term use, the inner surface becomes weakened and roughened, and the water flow rate is also large It is falling.
In addition, problems such as deterioration due to impurities such as earth and sand mixed in water and harmful substances such as acidic components, deterioration of the durability of concrete structures due to frost damage and ground subsidence, and water leakage from waterways due to cracks occur. ing.

In the repair of such a water channel, it is necessary to secure a necessary cross-sectional area of water even after the repair. Therefore, it is not preferable to repair the repair material with a thick repair material.
In general, the deterioration of the water channel is caused not only by surface abrasion but also by calcium leaching from the concrete, and a decrease in strength is observed from the concrete surface to several mm to several cm.

Thus, when repairing a concrete channel from which calcium has been leached, repair is performed after removing the deteriorated portion of the concrete by high-pressure water washing or the like, but it is difficult to completely remove the fragile layer.
Therefore, when repairing a deteriorated concrete channel, if the remaining fragile layer of the concrete is not reinforced, even if the repair material and the concrete structure are well bonded, the concrete fragile layer will easily peel off. Measures are needed.

Conventionally, as a repairing method for these concrete structures, a panel pasting method, a urethane resin spraying method, and a cross-sectional repairing method using a cement-based material are known.
The panel pasting method is a method of fixing an iron plate or FRP panel to a repaired portion with a bottle or the like.
Such a construction method has no fear of peeling at the remaining weak layer, and the smoothness of the repair surface is good, so the roughness coefficient is low, and therefore the water passage performance of the water channel after repair is high. The area is reduced and the water flow rate is reduced.
In addition, the panel to be pasted in advance has to be molded into an appropriate shape, and it is complicated to carry the panel into the repair location of the channel, to fix the panel connection part and to fix the panel to the channel base, There is a drawback in that many devices are necessary to perform these constructions.

In the urethane resin spraying method, a special spraying device is used and a work space for spraying is required. Therefore, the work is difficult in a narrow place and the workability is poor.
Furthermore, the sprayed repair membrane can secure the water flow rate without reducing the cross-sectional area of the channel, but even if the fragile layer portion does not remain, the adhesive strength on the concrete surface is not sufficient and the adhesion durability is improved. Inferior, there is a problem that it is easily peeled off from the concrete surface in places where it is constantly exposed to water flow.

In the cross-section restoration method using a cement-based material, polymer cement mortar with good adhesion to concrete is generally used, and it is excellent in workability and easy to handle.
However, with the conventional repair method using general-purpose polymer cement mortar, sufficient adhesion strength with the underlying concrete cannot be obtained due to the construction environment conditions, and the remaining concrete is peeled off at the fragile layer and repaired. When the surface is large, there is a problem that workability is poor because it cannot be applied thickly at once.
In addition, since the surface roughness after curing is not taken into consideration, it is often insufficient to ensure the water flow rate after repair.

In addition, there are materials that have insufficient wear resistance and contamination resistance, and when a material having a high drying shrinkage rate of cement mortar is used, fine cracks are generated on the surface of the repair mortar.
Such fine cracks are not only unfavorable in appearance due to the conspicuous cracks, but also cause water to get wet in the water channel, which adversely affects the impervious performance.

As a repair method for a water channel, Japanese Patent No. 3022708 proposes a curable composition comprising a hydraulic material, a polymer dispersion having a specific weight ratio and a methacrylate, and a method for applying the composition to the inner surface of the water channel. ing.
This method is intended to improve workability in a humid environment, but since the work is completed in a short period of time, it is difficult to ensure sufficient time for finishing work, and the roughness coefficient of the repaired mortar surface The problem of increased water resistance and water flow resistance has not been solved.
In order to improve this water flow resistance, it is necessary to further finish the top coat to reduce the water flow resistance, resulting in a complicated method.

JP-A-2001-213653 discloses a mortar composition produced by blending at a certain blending ratio with cement and fly ash using glass scraps having a specific particle size, and the mortar composition. A water channel repair method and a water channel structure using water is proposed.
Such a construction method exhibits performance that is excellent to some extent with respect to impact resistance and wear resistance, which are performances required for a water channel repair material.
However, the crack resistance due to the contraction of the concrete structure for a long time is inferior, and cracks are generated in the mortar, resulting in a problem of deterioration of water shielding performance and water permeation suppression performance. In addition, the problem of securing the water flow rate has not been solved.
Japanese Patent No. 3022708 Japanese Patent Laid-Open No. 2001-213653

  In view of the above-mentioned drawbacks, the object of the present invention is that in repairing concrete channels, the repair material is excellent not only in the concrete body after scratching the weakened layer of concrete but also in deteriorated or weakened concrete. Provided is a method for repairing a concrete water channel that can be integrated, has a low risk of peeling of repair materials, has good water shielding, crack resistance, water permeability and workability, and is particularly excellent in wear resistance.

In order to solve the above-mentioned problems, the present invention uses a concrete jointing epoxy resin adhesive as a primer for base concrete, and applies a specific polymer cement mortar having high wear resistance and low cure shrinkage ratio thereon. It was discovered that the construction method was effective.
That is, the concrete water channel repair method of the present invention includes a step of applying an epoxy resin adhesive and a step of repairing with a polymer cement mortar in repairing a concrete water channel, and after applying the epoxy resin adhesive, 100 parts by mass, 150 to 600 parts by weight of fine aggregate having an average particle diameter of 0.8 mm to 2.5 mm, 1 to 20 parts by weight of polymer for cement admixture, 1 to 20 parts by mass of expansion material, and 0 for shrinkage reducing agent Repairing method with polymer cement mortar containing 5 to 10 parts by mass, 0.1 to 3.0 parts by mass of long fibers and 0.1 to 3.0 parts by mass of fine fibers It is.

The concrete water channel repair method of the present invention is preferably repaired with polymer cement mortar in the above-mentioned concrete water channel repair method, after the epoxy resin adhesive is applied and before the epoxy resin adhesive is cured. It is characterized by this.
More preferably, in the method for repairing a concrete channel according to the present invention, the polymer cement mortar has a weight loss of 4 g or less in a Taber abrasion test after curing, and a rate of change in length after 91 days of placing is 0.05. % Or less.

According to the concrete water channel repairing method of the present invention, even when the weakened portion of the concrete water channel cannot be sufficiently suspended, there is less risk of peeling at the weakened layer portion of the concrete, and the concrete and the repair material Can be integrated with excellent adhesion, and can be used to repair a damaged concrete channel with a hardened material having good crack resistance and wear resistance.
Furthermore, according to the concrete water channel repair method of the present invention, it is possible to adjust the aggregate particle size distribution to ensure adaptability to various casting thicknesses, and to improve the water retention of the material, thereby preventing cracking resistance. , Integration with the housing, wear resistance is improved, and durability is secured and improved.
Furthermore, according to the concrete water channel repair method of the present invention, since the smoothness of the repair surface is good, the water flow performance of the concrete water channel after repair is high, and particularly excellent in wear resistance, so that the repair effect can be maintained over a long period of time. The effect is also obtained.

The present invention will be described in detail by the following preferred examples.
The repair method for a concrete channel according to the present invention includes a step of applying an epoxy resin adhesive and a step of repairing with a polymer cement mortar in repairing a concrete channel. 150 parts by weight of fine aggregate having an average particle diameter of 0.8 mm to 2.5 mm, 1 to 20 parts by weight of polymer for admixture of cement, 1 to 20 parts by weight of expansion material, and 0. This is a method of repairing with a polymer cement mortar containing 5 to 10 parts by mass, 0.1 to 3.0 parts by mass of long fibers, and 0.1 to 3.0 parts by mass of finely divided fibers.
By adopting such a construction method, the above-described effects can be effectively exhibited, and in particular, a concrete water channel having excellent wear resistance can be provided.

In the present invention, it is more preferable to carry out a step of removing the deteriorated portion of the concrete before applying the epoxy resin adhesive, if necessary.
For concrete waterways, especially bottom and side plates, surface wear and wear / defects due to mixed gravel and sand occur due to the influence of water flow, and the surface becomes brittle and rough, resulting in a decrease in water flow rate. In addition, there are problems such as acid deterioration due to impurities such as earth and sand mixed in water and harmful substances such as acidic components, deterioration of the durability of concrete structures due to frost damage and ground subsidence, water leakage from waterways due to cracks, etc. Therefore, it is desirable to preliminarily remove the weakened portion of the deteriorated concrete before applying the epoxy resin adhesive for repairing.
Any known method such as a method using a water jet using high-pressure water or a method using an electric pick is used to remove the deteriorated / fragile portion of the concrete channel.

In this way, it is desirable to suspend the deteriorated / weakened part in advance, but it is difficult to completely remove the fragile part of the concrete body, and it is fragile with the unfragile part of the concrete body. It is also difficult to distinguish between parts.
The concrete water channel repair method according to the present invention is a method that can reduce the risk of peeling at the weakened portion of the concrete body.

In repairing the concrete water channel, after removing the deteriorated portion of the concrete as required, an epoxy resin adhesive is uniformly applied to the portion as shown in FIG.
The epoxy resin-based adhesive has both the strength of the fragile layer of concrete, the integration with the joint mortar, and the adhesion durability.
Even if the weakened part of the concrete cannot be completely removed, the epoxy resin adhesive penetrates into the weakened layer and solidifies so that it has excellent adhesion to the repair mortar and is exposed to water for a long time. However, the adhesive performance does not deteriorate unlike a general-purpose aqueous adhesive.
As such an epoxy resin-based adhesive, for example, an epoxy obtained by mixing a main agent mainly composed of a liquid epoxy resin composition and a curing agent mainly composed of a liquid amine compound or an acid anhydride. Resin-based adhesives and the like can be suitably used, but at least one arbitrary epoxy resin-based adhesive for joining concrete can be used.

As an epoxy resin, if it is a conventionally well-known thing, arbitrary 1 or more types can be used.
For example, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type resin, bisphenol obtained by reacting biphenyl, bisphenyl A, bisphenyl F, bisphenyl AD, bisphenol S and the like with epichlorohydrin S-type epoxy resins, etc., hydrogenated or brominated epoxy resins, glycidyl ester type epoxy resins, novolac type epoxy resins, urethane-modified epoxy resins with urethane bonds, nitrogen-containing epoxidized metaxylenediamine, hydantoin, etc. An epoxy resin, a polybutadiene or a rubber-modified epoxy resin containing NBR can be used alone or in combination.

  Moreover, as a hardening | curing agent of an epoxy resin, if a conventionally well-known thing, arbitrary things can be used. For example, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, bishexamethylenetriamine, 1,3,6-trisaminomethylhexane, trimethylhexamethylenediamine, polyether diamine, diethylaminopropylamine, mensendiamine, Bis (4-amino-3-methylcyclohexyl) methane, N-aminoethylpiperazine, metaxylylene diamine, metaphenyl diamine, diaminodiphenyl sulfone, isophorone diamine, diaminodiphenyl methane alone and their modified products Or it can be mixed and used.

  Furthermore, phenol novolac, polymercaptan compound, polysulfide, ketimine compound, oxazolidine compound, tertiary amine compound, organic acid hydrazide, diandiamide and derivatives thereof, polyaminoamide, amine imide, carboxylic acid ester, boron trifluoride-amine complex, Use imidazole compounds, acid anhydrides, aliphatic acid anhydrides, halogenated acid anhydrides, aromatic diazinium salts, diallyl iodonium salts, triallyl sulfonium salts, rear allyl selenium salts alone or in combination. Can do.

As a method for applying such an epoxy resin adhesive to a concrete repaired portion, for example, an arbitrary application method using a brush, a roller, spraying, or the like is possible.
Since the mortar is applied immediately after application of the epoxy resin adhesive to immediately before curing, preferably immediately after application, if the coating amount is too large, the mortar applied on the top may be displaced. Yes, the application amount of the epoxy resin adhesive is preferably, for example, 200 to 1000 g / m ² .

Next, as shown in FIG. 1, after applying such an epoxy resin adhesive, it is repaired using a polymer cement mortar.
Such polymer cement mortar is applied on the applied epoxy resin adhesive and repaired immediately after the epoxy resin adhesive is applied and before the epoxy resin adhesive is cured. .

The polymer cement mortar used in the present invention comprises 100 parts by weight of cement, 150 to 600 parts by weight of fine aggregate having an average particle size of 0.8 mm to 2.5 mm, 1 to 20 parts by weight of polymer for mixing cement, and an expansion material. 1 to 20 parts by mass, 0.5 to 10 parts by mass of shrinkage reducing agent, 0.1 to 3.0 parts by mass of long fibers, and 0.1 to 3.0 parts by mass of finely divided fibers It is composed.
Specifically, the cement used in the polymer cement mortar used in the present invention can be selected in consideration of on-site construction conditions and the like, and is not particularly limited. For example, normal, early strong, moderately hot, and very early Various types of strong Portland cement, various mixed cements such as blast furnace cement obtained by mixing fly ash, blast furnace slag, and the like with these various Portland cements, fast-hardening cements, and the like can be used alone or in combination.
In particular, it is preferable to use early-strength cement because it is inexpensive and exhibits early strength.

  Also, known admixtures such as blast furnace slag powder, fly ash, silica fume, limestone powder, quartz powder, dihydrate gypsum, hemihydrate gypsum, and anhydrous gypsum can be added to the cement.

Moreover, as the fine aggregate used for the polymer cement mortar, river sand, sea sand, mountain sand, crushed sand, No. 3-8 silica sand, limestone, slag aggregate, etc. can be used. It is preferable to use fine aggregates such as silica sand and limestone whose particle size is adjusted and do not contain coarse aggregates.
The blending ratio is preferably 150 to 600 parts by mass, particularly preferably 200 to 450 parts by mass with respect to 100 parts by mass of the cement.
This is because, by mixing fine aggregates at such a blending ratio, in the present invention, the workability is further improved, practical strength development, and a repair material having a curing shrinkage that has no practical problem. Because.

Furthermore, the maximum particle size of the fine aggregate is 6 mm or less, and the average particle size of the fine aggregate is preferably 0.8 mm to 2.5 mm, more preferably 1.0 to 2.0 mm.
If the fine aggregate is less than 150 parts by mass with respect to 100 parts by mass of cement and the average particle size is less than 0.8 mm, cracking is likely to occur due to heat of hydration, and the iron finish will be poor, and 600 parts by mass will be reduced. If the average particle size is less than 0.8 mm, the amount of kneading water for the cement increases, the strength of the mortar decreases, and the resistance to wear may decrease.

  Further, when the average particle size is larger than 2.5 mm and the aggregate amount is less than 150 parts by mass, cracks are likely to occur, and the average particle size is larger than 2.5 mm and the aggregate amount is 600 parts by mass. This is because if the amount is too large, the surface finish becomes rough, and the roughness coefficient may increase.

Here, the average particle size is a value obtained by measuring the particle size distribution of fine aggregates using a sieve defined in JIS Z8801-1, and is an average particle based on a mass distribution represented by the following formula: The diameter M is shown.
M = (Σf _i · m _i ) / 100
Here, mi is sieve of magnitude of the average value of Neighboring, f _i is the mass percentage of particles remaining between old seeking m _i.
The maximum particle size means the size of the aggregate indicated by the nominal size of the smallest size sieve among the sieves through which 90% or more of the aggregate passes by mass.

Moreover, as a polymer for cement admixture used for the polymer cement mortar, for example, those specified in JIS A 6203 can be used, such as polyacrylate ester, styrene butadiene, ethylene vinyl acetate, vinyl acetate / vinyl versatate. Examples thereof include resins such as esters and vinyl acetate / versacic acid vinyl esters / acrylic acid esters, which can be appropriately selected from these and used alone or in combination.
In particular, when used for a member that requires durability such as water resistance, it is preferable to use a polyacrylate ester, and in consideration of reducing the measurement labor and measurement errors at the construction site, the re-emulsification type powder The use of a resin is preferred.

  The re-emulsified powder resin is a powder resin obtained by spray-drying a polymer dispersion specified in JIS A 6203, and emulsifies again when water is added. The polymer dispersion is a dispersion of the above-mentioned polymer fine particles in water. As a method for stabilizing the polymer in a floating state, for example, a carboxyl method (anionization method) for copolymerizing acrylic acid, a water-soluble polymer, for example, polymerization in an aqueous solution such as polyvinyl alcohol There are a protective colloid method, a copolymerization method with a polymerization reactive surfactant, and a stabilization method with a non-polymerization surfactant.

The method for producing such a re-emulsified powder resin is not particularly limited, and these polymer dispersions can be prepared using any known method such as a powdering method or an anti-blocking method.
The re-emulsified liquid of the re-emulsified powder resin preferably has a minimum film forming temperature of 0 ° C. or higher.
When the minimum film-forming temperature is 0 ° C. or higher, the adhesion with concrete is improved and the surface hardness of the polymer cement mortar is hard, and the early strength development is excellent.

As a compounding quantity of this polymer (solid content) for cement mixing, 1-20 mass parts is mix | blended with respect to 100 mass parts of cement, It is desirable that it is 2-10 mass parts suitably.
By mixing a cement admixing polymer, preferably a re-emulsifying powder resin, at this blending ratio, it has better adhesion to concrete when used as a polymer cement mortar. .
If the polymer is less than 1 part by mass with respect to the cement, the adhesion performance with concrete cannot be sufficiently exhibited, and the water shielding performance of the mortar becomes small. If the polymer exceeds 20 parts by mass, the fluidity of the polymer cement mortar and This is because the strength is lowered, there is a possibility that the performance as a repair material of the concrete structure may be hindered, and workability may be deteriorated.

  As an expansion material used for the above polymer cement mortar, for any concrete such as calcium sulfoaluminate, quicklime, gypsum, quicklime-gypsum, lime-ettringite composite, iron powder, magnesium and aluminum powder It is not particularly limited as long as it can use one or more inflatable materials, can appropriately expand the cross section after repair, and can compensate for cracks due to drying shrinkage, and uses a known or commercially available product. be able to.

The amount of the expansion material is 1 to 20 parts by mass, preferably 2 to 10 parts by mass with respect to 100 parts by mass of cement.
By setting this range, it is possible to effectively compensate for cracks due to drying shrinkage. If the amount is less than the above range, cracking may occur due to shrinkage, and if it is more than the above range, cracking or peeling due to expansion may occur.

Further, the polymer cement mortar contains a drying shrinkage reducing agent.
Such a drying shrinkage reducing agent has a function of greatly reducing the surface tension of the solution in a strong alkaline solution.
As the drying shrinkage reducing agent, those mainly composed of a lower alcohol alkylene oxide adduct, a glycol ether / amino alcohol derivative, a polyether, an ether type nonionic surfactant, a low molecular weight alkylene oxide copolymer and the like can be used. Any one or more drying shrinkage reducing agents can be used as long as the drying shrinkage can be reduced by reducing the surface tension in a strong alkaline solution regardless of the composition and shape (liquid or powder). be able to.
The mixing amount of the drying shrinkage reducing agent is 0.5 to 10.0 parts by mass, preferably 1.0 to 6.0 parts by mass with respect to 100 parts by mass of cement.
If it is less than 0.5 parts by mass, the drying shrinkage reduction effect is small and crack resistance may be inferior, and even if it exceeds 10.0 parts by mass, the drying shrinkage reduction effect is hardly changed, which is economical. Because there is no.

Further, the polymer cement mortar includes 3 to 12 mm long fibers and fine powder fibers.
Examples of such fibers include alkali-resistant glass fibers, carbon fibers, aramid fibers, vinylon fibers, polypropylene fibers, polyethylene fibers, acrylic fibers, and the like, and at least one of these can be used.
The length of the long fiber is preferably 3 to 12 mm. When the length of the fiber is shortened, the effect of inhibiting cracking is lowered, and when the length is long, the kneadability with water and the workability are deteriorated.
The length and diameter of the finely divided fiber are not particularly limited as long as they can impart thixotropy.
If the polymer cement mortar does not have an appropriate thixotropy, when the mortar is applied to the side wall, sagging occurs, and good construction becomes difficult.
In addition, when fine powder fibers are not mixed, the material is inferior in crack resistance.

  In the polymer cement mortar used in the present invention, in addition to the above materials, additives such as a setting retarder, a curing accelerator, a thickener, an antifoaming agent, a foaming agent, a rust inhibitor, a defrosting agent, a colorant, It can be used as long as the object of the present invention is not substantially inhibited.

In addition, the polymer cement mortar used in the method of the present invention is kneaded by adding an appropriate amount of water to the above material, but if the water does not contain components that adversely affect the hardening of cement or the like, tap water or groundwater Water such as river water can be used. For example, water that is compatible with “JIS A 5308 Appendix 9 Water used for kneading ready-mixed concrete” is preferable, but water contained in the admixture can also be used. Is possible.
In order for the amount of water to be adjusted so that the water / cement mass ratio is 0.3 to 0.6, preferably 0.35 to 0.55, the above effect can be expressed more effectively. preferable.
In addition, when water is used as the polymer dispersion, the water / cement mass ratio including such water is taken into consideration.

The polymer cement mortar of the present invention may be mixed at the time of construction or a part of it may be mixed in advance, but it is possible to mix the material mixed with the powder component and water at the construction site. This is preferable because it eliminates the need for weighing and measuring errors.
The apparatus for premixing the powder component is not particularly limited as long as it can be uniformly mixed, and any existing apparatus can be used, for example, a Henschel mixer, an omni mixer, a V-type mixer, a nauter mixer, etc. It is done.

  The polymer cement mortar thus obtained can be applied by, for example, troweling, spraying, etc., and applied to a wall thickness of about 10 mm at a time in wall construction as in the case of generally used repair mortar. Is possible. There is no particular limitation on the construction method.

The polymer cement mortar filled in this way can have good surface smoothness as shown in FIG. 1 by performing, for example, ironing after the construction.
The iron leveling can be performed with the use of water, a curing agent, or the like on the surface of the cement mortar to further improve the smoothness.

In the concrete water channel after the repair to which the concrete water channel repair method according to the present invention is applied as described above, the surface roughness of the obtained polymer cement mortar cured product can be 600 μm or less, preferably 400 μm or less. This makes it possible to ensure good water permeability.
However, the surface roughness is a value measured by a finger touch type three-dimensional measuring instrument (PICAZA PIX-30 manufactured by Roland DG Co., Ltd.).
Further, the polymer cement hardened material of the concrete channel after repairing using the concrete channel repairing method of the present invention has a wear loss of 4 g or less in the Taber type abrasion resistance test according to JIS K 7240, which will be described later. In the crack acceleration test described in the examples, no cracks are generated.
Therefore, it is extremely excellent in wear resistance and can be maintained for a long time after repair.
Furthermore, the length change rate of the polymer cement mortar cured product of the concrete channel after repairing to which the concrete channel repairing method of the present invention is applied is set in 91 in the length change measuring method test according to JIS A 1129, which will be described later. The rate of change in length after a day is 0.05% or less, and it has excellent crack resistance and can be maintained for a long time after repair.

In addition, the concrete water channel repair method of the present invention carried out in this way is easy to construct, has good workability, is useful for repair of water channels in the field of construction and civil engineering, and is sufficient to lift weakened parts. Even if it is not possible, there is little risk of delamination at the fragile layer portion of concrete, the concrete and the repair material can be integrated with excellent adhesion, and crack resistance and wear resistance are good It is a hardened material.
Furthermore, according to the concrete water channel repair method of the present invention, since the smoothness of the repair surface is good, the water flow performance of the concrete water channel after repair is good, and the effect of being able to be maintained for a long time because of excellent wear resistance. It is done.

The present invention will be illustrated by the following examples, comparative examples and test examples, but is not limited thereto.
A. Materials used Examples and comparative examples were carried out using the following materials.
1) Adhesive The adhesive shown in Table 1 was used.

2) Using each material shown in Table 2 and mixing at the blending ratio shown in Table 5 adjusted so that the consistency is substantially the same, and stirring and kneading uniformly according to JIS A 1171, cement Mortar was prepared.
However, as the particle size-adjusted sand (aggregate) in Table 2, a mixture of fine aggregates having the particle size distribution shown in Table 3 (representing the remaining amount of sieving) in the ratio shown in Table 4 was used.
These silica sands were all manufactured by Nippon Steel Industry Co., Ltd.
Table 4 also shows the average particle size of the obtained particle size-adjusted sand.

The particle size distribution is measured using a sieve specified in JIS Z 8801-1, and the average particle size is an average particle size M based on mass distribution represented by the following formula. .
M = (Σf _i · m _i ) / 100
Here, mi is sieve of magnitude of the average value of Neighboring, f _i is the mass percentage of particles remaining between old seeking m _i.

Examples 1-2 and Comparative Examples 1-12
For the adhesion performance test, a concrete repairing method was carried out using the concrete adhesive and each cement mortar with the combinations and blending ratios shown in Table 5 above.

Adhesion performance test The adhesion performance test was conducted by immersing a 300 x 300 x 60 mm JIS A 5371 normal flat plate as a base plate in 0.1N hydrochloric acid for 6 hours to weaken the surface of the flat plate, and then passing it for 3 months. It left still under the water flow of 0.1 m < ³ > / min, and the surface was worn by the said water flow.
Thereafter, each of the adhesives of Examples 1-2 and Comparative Examples 1 and 3-12 shown in Table 5 was applied to the flat plate which had been dried at 20 ° C. and humidity of 60% for 7 days or more using a brush. Apply thinly at ² and immediately after application, that is, before the adhesive is solidified, each polymer cement mortar is uniformly applied with a trowel with a thickness of 1 cm, and cured for 28 days at 20 ° C. and 60% humidity to repair. The test specimens were obtained.
In Comparative Example 2, a test specimen was prepared by directly applying polymer cement mortar to the above-treated flat plate without applying an adhesive.

Each test specimen was cut until a 40 × 40 mm incision reached the concrete plate, and the steel attachment was bonded with an epoxy resin adhesive, and then the Kenken-type adhesion test device (LPT-3000, The adhesive strength was measured using Oxjack Co., Ltd.
As evaluation of the measurement result, 1.5 N / mm ² or more was evaluated as “◯”, and less than 1.5 N / mm ² was evaluated as “x”.
The results are shown in Table 6.

Crack resistance test The crack resistance test was carried out in a wind tunnel immediately adjusted to a wind speed of 3 m / sec after the same test specimens (Examples 1-2 and Comparative Examples 3-12) used in the adhesion performance test were prepared. The test specimen was placed so as to be parallel to the airflow, and the specimen was taken out after 6 hours, and the presence or absence of cracks was evaluated visually.
About the test body in which the crack was not visually confirmed, it was further cured for 28 days at 50 ° C. and a humidity of 40%, and water was sprayed on the construction surface to evaluate the presence or absence of the crack.
As the evaluation of the above measurement results, “×” indicates that cracks were confirmed after 6 hours, “△” indicates that cracks were confirmed after curing at 50 ° C. for 28 days, and “○” indicates that cracks were not confirmed. Table 6 shows the results.

Length change rate Using each cement mortar shown in Table 5 used in the above Examples 1-2 and Comparative Examples 3-12, in a constant temperature room at a temperature of 20 ° C., it was molded into a shape of 40 × 40 × 160 mm, 24 After demolding after time, the base length was measured immediately, followed by curing at a temperature of 20 ° C. and a humidity of 60% for 91 days, and the length change rate was tested.
The test was measured according to the dial gauge method of JIS A 1129 (Method for measuring change in length of mortar and concrete), and the rate of change in length was evaluated.
As the evaluation of the above measurement results, a length change rate of 0.05% or less was evaluated as “◯”, and a length change rate larger than 0.05% was evaluated as “X”.

Abrasion resistance Using each cement mortar shown in Table 6 used in Examples 1-2 and Comparative Examples 3-12, cylindrical bodies of φ100 mm × 200 mm were prepared, and after curing at 20 ° C. and 60% humidity for 28 days. Each specimen was cut out with a thickness of 10 mm from the placement surface (upper surface of the specimen).
Wear resistance was evaluated by using the cut surface of the cut specimen having a thickness of 10 mm as the following wear test surface.
Using a Taber type abrasion tester (rotary abrasion tester, manufactured by Toyo Seiki Seisakusho Co., Ltd.), a wear test is performed under the following conditions in accordance with JIS K 7204, and the weight of the test specimen before and after the test is measured to calculate the wear loss. The wear resistance was evaluated.
Wear wheel H-22
Load 1000g
Rotation speed 1000 rotations As an evaluation of the above measurement results, wear loss of 4 g or less was evaluated as “◯”, and those larger than 4 g were evaluated as “x”, and Table 6 shows the results.

Surface roughness Using each cement mortar shown in Table 6 used in Examples 1-2 and Comparative Examples 3-12 above,
Each flat plate of 200 × 100 × 30 mm was prepared, and after curing for 28 days at 20 ° C. and 60% humidity, each specimen was used.
The surface roughness of each test specimen was measured using the following surface roughness test surface.
However, the roughness is determined by using the stylus type three-dimensional measuring instrument (product number PICAZA PIX-30 manufactured by Roland DG Co., Ltd.) for the surface of each obtained test specimen (100 × 50 mm). ) Is measured at intervals of 0.5 mm, and is represented by the arithmetic average roughness (Ra).
As the evaluation of the above measurement, the evaluation was made as “◯” for less than 400 μm, “Δ” for 400 μm or more and less than 600 μm, and “X” for 600 μm or more.

  The concrete water channel repair method of the present invention can be effectively applied to repair of the inner surface of various water channels such as dam conduits, water discharge channels, agricultural and industrial water channels, and water and sewer pipes, and in particular, repair of bottom plates and side plates of water channels. It is widely used in the civil engineering and construction industries.

The figure which shows roughly the repair location which implemented the repair method of the concrete water channel of this invention.

Claims (3)

  In repairing the concrete water channel, including the step of applying an epoxy resin adhesive, the step of repairing with a polymer cement mortar, after applying the epoxy resin adhesive, 100 parts by mass of cement, average particle size 0.8mm ~ 150 to 600 parts by weight of a 2.5 mm fine aggregate, 1 to 20 parts by weight of a polymer for mixing cement, 1 to 20 parts by weight of an expansion material, 0.5 to 10 parts by weight of a shrinkage reducing agent, and 0 to long fibers A repair method for a concrete channel, comprising repairing with a polymer cement mortar containing 0.1 to 3.0 parts by mass and 0.1 to 3.0 parts by mass of finely divided fibers.   The method for repairing a concrete channel according to claim 1, wherein after the epoxy resin adhesive is applied, the concrete channel is repaired with a polymer cement mortar before the epoxy resin adhesive is cured. . 3. The method for repairing a concrete channel according to claim 1 or 2, wherein the polymer cement mortar has a wear loss in a Taber abrasion test after curing of 4 g or less and a rate of change in length after 91 days of placement of 0.05% or less. A concrete waterway repair method, characterized by being.

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