JP5909178B2 - Injection material for repairing cracks in concrete, method for manufacturing the same, and injection method using the same - Google Patents

Description

  The present invention is an injection material for repairing concrete cracks, a method for producing the same, and an injection method using the same, and in particular, has excellent permeability even for fine concrete cracks of 100 μm or less, and has a high water-stopping effect. Further, the present invention relates to an injection material for repairing cracks in concrete that can obtain durability and durability, a manufacturing method thereof, and an injection method using the same.

  Concrete often cracks due to temperature shrinkage during curing, temperature change after curing, and drying. And even if it is a fine crack of 100 μm or less, which does not cause a problem in appearance, water penetrates from the crack of the concrete or leaks the contained gas, so repair the fine crack of concrete of 100 μm or less. There is a need for an injection material.

  2. Description of the Related Art Conventionally, a solution-type silica injection material using water glass as a raw material is known as a highly permeable injection material for cracks in concrete. For example, a water glass alkaline injection material, an injection material mainly composed of acidic silica sol, an injection material mainly composed of active silica obtained by treating water glass with a cation exchange resin or an ion exchange membrane, and active silica Silica colloidal injection materials and the like that have been concentrated and granulated and have a pH of 9 to 10 and have been stabilized with weak alkali have been used (Patent Documents 1 and 2).

However, under high water pressure, the above-described solution-type silica injecting material has a strength (homogen strength) of the injecting material as small as 0.01 N / mm ² or less. There was a problem that water stoppage and long-term durability were reduced.

  Ultrafine cement may be used in place of the solution type silica injection material, but the average particle size of the fine particle cement is as large as about 5 μm. Therefore, the permeability to concrete cracks of 100 μm or less is poor and better. Therefore, there is a demand for an injection material having high permeability, water stop effect, and durability (Patent Document 3).

In addition, an injection material mainly composed of fine-particle silica has been proposed (Patent Document 4).
Patent Document 4 describes that an injection material mainly composed of fine particle silica, which is a material A, is injected into the ground.
However, when the fine particle silica is injected into the cracks in the concrete, it may react instantaneously with the alkali in the concrete, and the permeability to the cracks in the concrete may not be ensured. And in patent document 4, when it inject | pours into the crack of concrete, there is no description about the permeability to the crack of concrete being ensured, without reacting with the alkali in concrete instantly.

Then, the ground injection material which consists of fine particle silica, an alkaline hardening material, water, and carboxylic acid or its salt was proposed (patent document 5).
As described in the Examples of Patent Document 5, the above ground injection material has a very long curing time, has no fluidity even at a material age of 3 days, and is so small that the compressive strength cannot be measured. And in patent document 5, even if it inject | pours into the crack of concrete like this invention, it is the description about the permeability to a crack of concrete, and water stoppage not reducing without the injection material being extruded by water pressure. There is no.

Moreover, the construction method of the injection material which inject | pours separately the A material containing a pozzolanic substance and water, and the B material containing a calcium containing substance and water is proposed (patent document 6).
Patent Document 6 includes "a method for applying an injection material in which a material A previously containing a pozzolanic substance and water and a material B previously containing a calcium-containing material and water are separately injected" (Claim 1); The invention according to claim 1, wherein the A material contains a dispersant in advance. (Claim 2) is described, and "in addition, a dispersant is used in combination with the B material in order to improve dispersibility." (Paragraph [0014]), but there is no specific description about using a dispersant in combination with a calcium-containing substance and water-containing B material, and the A material and the B material. In the case of simultaneous injection, the injection material hardened immediately, and there was a problem that injection could not be performed (paragraph [0022]). In addition, as a pozzolanic substance, it has been shown that “spherical silica obtained by melting a raw material silica stone having an average particle size of 1 μm or less into a spherical shape by melting it in a high-temperature flame” is used. It is not shown that the average particle size of silica is 1 μm or less. Neither is it shown that the calcium-containing material is ground and dispersed to 1 μm or less. That is, in Example 2 of Patent Document 6, the dispersant is used in combination with the A material, but not in the B material. If the A material and the B material are mixed as they are, the A material and the B material need to be injected separately, and the uniformity of the injected material could not be maintained. Further, Patent Document 6 does not show that the calcium-containing substance is pulverized to 1 μm or less and dispersed.

  Moreover, although patent document 7 has description of a silica, lime, and a dispersing agent, there is no description of containing a dispersing agent in each of the suspension containing silica and the suspension containing lime.

Patent Document 8 states that “the addition of water and a dispersant to a powdered ultrafine particle material, pulverizing and stirring the ultrafine particle material, adding a dispersant, pulverizing and stirring the ultrafine particle material. Add water and a dispersant to the ultra-fine particle material of powder different from the high-dispersion low-viscosity ultra fine particle slurry of No. 1 and the first highly dispersed low-viscosity ultra fine particle slurry, and disintegrate the ultra-fine particle material Then, a dispersant is added, and the ultrafine particle material is crushed and mixed with the second highly dispersed low viscosity ultrafine particle slurry, and the ultrafine particle material is crushed and stirred. And a method of producing a highly dispersed low-viscosity ultrafine particle slurry characterized by adding, crushing and stirring the ultrafine particle material. (Claim 3), wherein the ultrafine particle material is silica fume and / or Or slaked lime ”(claim 6, paragraph [0034], [ 068]), and the primary particle average particle size of silica lime (slaked lime / silica fume = 1) measured by a laser diffraction / scattering particle size analyzer is 0.10 μm (paragraphs [0068] and [0072] Tables) 1) It is also described that the permeability is 100% when the average aggregated particle size is about 1 μm or less ([0070]).
However, in the invention described in Patent Document 8, in order to set the average particle size to 1 μm or less, as described above, the crushing of ultrafine particle materials (silica fume and slaked lime), stirring, and addition of a dispersant are repeatedly performed. In order to produce a highly dispersed low-viscosity ultrafine particle grout that is close to primary particles, as a crushing method, slurry is mixed with a ball (bead) as a medium. It was necessary to apply the method of stirring (paragraph [0021]). And when measuring using a laser diffraction / scattering type particle size analyzer, an ultrasonic dispersion process is usually performed as a pre-processing, and therefore, a laser diffraction / scattering type particle size analyzer without performing the ultrasonic dispersion process. The average particle size when measured using is not clear. In addition, there is no description of fine silica powders other than silica fume as the ultrafine particle material, and there is no description about durability when a highly dispersed low viscosity ultrafine particle slurry is used as an injection material.

  In Patent Documents 9 and 10, a slurry in which a metal silicon powder concentration in which metal silicon powder is dispersed in water is 20 to 70%, or 5 to 60% is at least 10 m / second or more, or at least 20 m in a flame. Although a fine silica powder (fine spherical silica) produced by a method of injecting, burning, and oxidizing at a protruding speed of at least / sec is shown, it is not shown that these fine spherical silicas are used as an injection material.

  Non-Patent Document 1 describes a grout material (injection material) comprising a mixture of agent A containing ultrafine spherical silica and water, and agent B containing ultrafine calcium hydroxide, a dispersant and water. However, there is no description about adding a dispersing agent to the agent A, and if the amount of ultrafine calcium hydroxide added is increased, the fluidity decreases, so the mixing ratio of agent A and agent B is limited. There was a problem. In addition, the particle sizes of ultrafine spherical silica and ultrafine calcium hydroxide are each shown to be approximately 1 μm or less. However, when measuring the particle size distribution, ultrasonic dispersion treatment is usually performed as a pretreatment. The average particle size when the particle size distribution is measured without performing ultrasonic dispersion treatment is not clear.

Japanese Patent No. 3205900 JP 2004-035584 A JP 2006-226014 A JP 2007-217453 A JP 2008-120892 A JP 2009-299291 A International Publication No. 2005/123623 Japanese Patent Laid-Open No. 08-041455 JP 2001-354409 A JP 2002-020113 A

Outline of the 64th Annual Conference of the Japan Society of Civil Engineers (CD-ROM) August 3, 2009, pages 145-146

  An object of the present invention is to provide a concrete crack repairing injection material that exhibits high water permeability and exhibits excellent water-stopping effect and durability even for cracks in concrete of 100 μm or less, a method for producing the same, and a method for using the same. It is to provide an injection method.

The present invention employs the following means in order to solve the above problems.
(1) A wet-dispersed A material containing fine particle silica having an average particle size of 1.0 μm or less, a dispersant, a polymer dispersion, and water, and a calcium compound and dispersant having an average particle size of 1.0 μm or less And a wet cracking and dispersing B material containing water, and a concrete crack repairing injection material, wherein the fine particle silica concentration is 40 to 70%, and the polymer dispersion is ethylene- It consists of a vinyl acetate copolymer or a styrene butadiene copolymer, 0.1 to 10 parts by mass in terms of solid content, and the calcium compound has a concentration of 30 to 60% with respect to 100 parts by mass of the fine particle silica. It is an injection material for repairing cracks in concrete, which is 50 to 100 parts by mass with respect to 100 parts by mass of silica.
( 2 ) The average particle size of the fine particle silica and the calcium compound is an average particle size measured using a laser diffraction particle size distribution meter without performing ultrasonic dispersion treatment . It is an injection material for repairing cracks in concrete.
( 3 ) The concrete crack repairing injection material according to (1) or (2) , wherein the fine particle silica is fine particle spherical silica having an average sphericity of 95% or more.
( 4 ) The concrete crack repairing injection material according to any one of (1) to ( 3 ), wherein the calcium compound is calcium hydroxide.
( 5 ) Said (1)-( 4 ) characterized by the usage-amount of the dispersing agent in said A material being 0.1-30 mass parts in conversion of solid content with respect to 100 mass parts of fine particle silica. It is an injection material for the crack repair of concrete of any one of these.
( 6 ) Of the above (1) to ( 5 ), the amount of the dispersant used in the B material is 1 to 30 parts by mass in terms of solid content with respect to 100 parts by mass of the calcium compound. 4. An injection material for repairing cracks in concrete according to any one of the above.
( 7 ) Furthermore, 0.1-10 mass parts of hardening time regulators are contained with respect to 100 mass parts of said calcium compounds, Any one of said (1)-( 6 ) characterized by the above-mentioned. It is an injection material for repairing cracks in concrete according to item 1.
( 8 ) An ethylene-vinyl acetate having an average particle size of 1.0 μm or less and 0.1 to 10 parts by mass in terms of solid content with respect to 100 parts by mass of fine particle silica having a concentration of 40 to 70% and the fine particle silica. A suspension containing a polymer dispersion comprising a copolymer or a styrene-butadiene copolymer and water is prepared, and a dispersing agent is added to this suspension, and water is mixed if necessary, and wet dispersion treatment is performed. On the other hand, the average particle diameter is 1.0 μm or less, the concentration is 30 to 60%, and 50 to 100 parts by mass of the calcium compound, the dispersant, and 100 parts by mass of the fine-particle silica. A suspension containing water is prepared, and further, water is mixed with this suspension as necessary to produce a B material that has been wet pulverized and dispersed, and the A material and the B material are mixed. Concrete crack characterized by that It is a manufacturing method of repair grout.
( 9 ) The concrete crack repairing of ( 8 ) above, wherein the fine particle silica is produced by a method in which a slurry in which metal silicon powder is dispersed in water is injected into a flame and burned and oxidized. It is a manufacturing method of an injection material.
( 10 ) The average particle diameter of the fine particle silica and the calcium compound is an average particle diameter measured using a laser diffraction particle size distribution meter without performing ultrasonic dispersion treatment, ( 8 ) or It is a manufacturing method of the injection material for crack crack repair of concrete of ( 9 ).
( 11 ) The concrete crack repair injection according to any one of ( 8 ) to ( 10 ), wherein the fine particle silica is fine particle spherical silica having an average value of sphericity of 95% or more. It is a manufacturing method of material.
( 12 ) The method for producing an injection material for repairing a crack in concrete according to any one of ( 8 ) to ( 11 ), wherein the calcium compound is calcium hydroxide.
( 13 ) Of the above ( 8 ) to ( 12 ), the A material and / or the B material are wet-dispersed and / or wet-pulverized / dispersed using a pulverizer using high-pressure water. It is a manufacturing method of the injection material for the crack repair of concrete of any one term.
( 14 ) The use amount of the dispersant in the A material is 0.1 to 30 parts by mass in terms of solid content with respect to 100 parts by mass of fine-particle silica, ( 8 ) to ( 13 ) It is a manufacturing method of the injection material for crack crack repair of any one of these.
( 15 ) Of the above ( 8 ) to ( 14 ), the amount of the dispersant used in the B material is 1 to 30 parts by mass in terms of solid content with respect to 100 parts by mass of the calcium compound. The method for producing an injection material for repairing a crack in concrete according to any one of the above.
( 16 ) Furthermore, 0.1-10 mass parts of hardening time regulators are contained with respect to 100 mass parts of said calcium compounds, Any one of said ( 8 )-( 15 ) characterized by the above-mentioned. It is a manufacturing method of the injection material for crack crack repair of concrete of 1 term.
( 17 ) An injection method characterized by injecting the concrete crack repairing material according to any one of (1) to ( 7 ).
(18) wherein the A member and the B member, one shot method, mixed by any of the methods 1.5 shot method, and two-shot method, above, wherein the injection into cracks in concrete (17 ) Injection method.

  INDUSTRIAL APPLICABILITY According to the present invention, in concrete having fine cracks of 100 μm or less, high permeability to concrete cracks is obtained, and an injection material for repairing concrete cracks having an excellent water-stopping effect and excellent durability, and a method for producing the same And an injection method using the same can be provided.

Hereinafter, embodiments of the present invention will be specifically described.
Unless otherwise indicated, parts and% described in the present invention mean parts by mass and% by mass.

  In the present invention, fine particle spherical silica powder produced by a method in which a slurry in which metal silicon powder is dispersed in water is injected into a flame and burned and oxidized is used as fine particle silica. This fine-particle spherical silica is preferable in that it has less agglomeration (structure) and has high permeability to concrete cracks.

  In the present invention, the particle size of the fine particle silica is not particularly limited as long as a desired effect is obtained, but the average particle size is 1.0 μm or less from the viewpoint of improving the permeability to concrete cracks and the compressive strength. However, 0.05 to 0.8 μm is preferable. For example, in a high-temperature flame formed by combustible gas and auxiliary combustion gas, a slurry in which metal silicon powder is dispersed in water and having a metal silicon powder concentration of 5 to 70% is injected at a protruding speed of at least 10 m / sec. Then, spherical silica powder is produced by melt spheronization. Furthermore, fine particle spherical silica powder having an average particle diameter excellent in fluidity promoting effect can be collected by classification treatment. For example, it can manufacture by the method of patent documents 9-10.

  In addition, the fine particle silica has an average value of sphericity of preferably 90% or more, more preferably 95% or more, and particularly preferably 97% or more from the viewpoint of improving permeability and compressive strength.

The sphericity can be measured using a scanning electron microscope (“JSM-T200 type” manufactured by JEOL Ltd.) and an image analyzer (manufactured by Nippon Avionics Co., Ltd.). For example, first, the projected area (A) and the perimeter (PM) of particles are measured from an SEM photograph of powder. When the area of a perfect circle corresponding to the perimeter (PM) is (B), the sphericity of the particle can be displayed as A / B × 100 (%). Therefore, assuming a perfect circle having the same circumference as the sample particle (PM), PM = 2πr and B = πr ² , so that B = π × (PM / 2π) ² , and each particle Can be calculated as sphericity = A / B × 100 (%) = A × 4π / (PM) ² × 100 (%), so the average value of 200 arbitrary particles is the sphere of the powder. It can be calculated as a degree.

  Examples of the fine particle silica include trade names “SFP-20M” and “SFP-30M” manufactured by Denki Kagaku Kogyo Co., Ltd., and trade names “Admafine” manufactured by Admatech.

Examples of the calcium compound of the present invention include calcium hydroxide, calcium chloride, inorganic substances such as gypsum, and calcium salts of organic acids such as calcium formate. Among these, calcium hydroxide is preferable in terms of improving compressive strength.
When the calcium compound is calcium hydroxide, it is a fine product manufactured by a so-called build-up method in which a soluble calcium salt such as calcium chloride and a soluble alkali salt such as sodium hydroxide and potassium hydroxide are dissolved and mixed. Calcium hydroxide can also be used.

  In the present invention, the calcium compound is pulverized to an average particle size of 1.0 μm or less from the viewpoint of permeability to concrete cracks and improved compressive strength, but is pulverized to an average particle size of 0.05 to 0.8 μm. It is preferable.

  In the present invention, the fine particle silica and the calcium compound are dispersed in water, respectively, to produce the A material and the B material, respectively.

The concentration of particulate silica in the material A of the present invention is 40% to 70%, is good preferable 20% to 60%. When the concentration of the fine particle silica exceeds 80%, the viscosity becomes high and the permeability to concrete cracks may be lowered. Moreover, in this invention, it is also possible to manufacture a high concentration fine particle silica slurry beforehand, and to dilute and use with water at the time of construction. Moreover, when it does not permeate at a high concentration, it can be surely injected into small concrete cracks by continuing to inject for a long time at a low concentration of 10% or less, and a high improvement effect can be obtained.

The concentration of calcium compound B material of the present invention is 30-50%, is good preferable 10-40%. If the concentration of the calcium compound exceeds 60%, the viscosity becomes high and the permeability to cracks in the concrete may decrease. Moreover, in this invention, it is also possible to manufacture a high concentration calcium compound slurry beforehand and to dilute with water at the time of construction.

The amount of calcium compound B material of the present invention, 100 parts finely divided silica, a 5 0-100 parts. If the amount of the calcium compound is less than 20 parts, the compressive strength may be reduced, and if it exceeds 200 parts, the permeability to concrete cracks may be reduced. Moreover, in this invention, it is also possible to manufacture a high concentration calcium compound slurry beforehand and to dilute with water at the time of construction.

In the present invention, it is necessary to use a dispersant in each of the A material and the B material. If a dispersant is added only to the A material or only to the B material, it is unfavorable because it reacts and solidifies at the moment of mixing with the other liquid. However, depending on the state of injection, the gel time can be shortened or reduced by reducing the amount of dispersant used, which can be used for leak prevention or limited injection.
The reason why good permeability can be obtained when the dispersant is used for both the A material and the B material is unknown, but immediately after the dispersant reacts on the surface of the fine particle silica or calcium compound and the fine particle silica and the calcium compound come into contact with each other. This is thought to be because the cure is delayed so as not to cause a hydration reaction.

  As the dispersant used in the present invention, naphthalene sulfonic acid-based dispersant, lignin sulfonic acid-based dispersant, melamine sulfonic acid-based dispersant, polycarboxylic acid-based dispersant, and polyether-based dispersant can be used. Of these, naphthalene sulfonic acid-based dispersants or melamine sulfonic acid-based dispersants are preferred from the viewpoints of permeability to concrete cracks and improvement in compressive strength.

The amount of the dispersant for the A material used is preferably 0.1 to 30 parts, and more preferably 1 to 10 parts in terms of solid content with respect to 100 parts of the fine particle silica of the A material. If it is less than 0.1 part, it reacts and solidifies at the moment when it is mixed with the other liquid, and the permeability to cracks in concrete may be poor, and if it exceeds 30 parts, the compressive strength may be low.
Fine particle silica produced by injecting a slurry of metal silicon powder in water into a flame, burning and oxidizing it has good dispersibility and can be dispersed in water without first adding a dispersant. Therefore, a dispersant may be added later. This water dispersibility is presumed to be related to the silanol group concentration.

  The amount of the dispersant for the B material used is preferably 1 to 30 parts, more preferably 5 to 20 parts in terms of solid content with respect to 100 parts of the calcium compound. If it is less than 1 part, it reacts and solidifies at the moment of mixing with the other liquid, and the permeability to cracks in the concrete may be poor, and if it exceeds 30 parts, the compressive strength may be low.

  In order to improve the permeability to concrete cracks, the fine-particle silica and the calcium compound are preferably dispersed or pulverized and dispersed by various wet pulverizers. The average particle size referred to here is usually a suspension obtained by wet dispersion treatment or wet pulverization dispersion treatment using a laser diffraction particle size distribution analyzer (for example, “LA-920 type” manufactured by HORIBA, Ltd.) It is the value measured in the aqueous medium without performing the ultrasonic dispersion treatment performed as the pretreatment. When the average particle size of the fine particle silica and calcium compound measured without performing ultrasonic dispersion treatment is 1.0 μm or less, the fine particle silica hardly aggregates. Therefore, the injection material of this invention improves the permeability to the crack of concrete. The suspension subjected to wet dispersion treatment or wet pulverization dispersion treatment refers to, for example, A material obtained by wet dispersion treatment of fine particle silica and B material obtained by wet pulverization dispersion treatment of calcium hydroxide.

  The wet pulverizer used when the A material is wet-dispersed and the B material is wet-pulverized and dispersed may be any of a high-speed stirrer, a medium agitating mill, and a pulverizer using high-pressure water. Among these wet pulverizers, in particular, the dispersibility of fine-particle silica is improved, and the shape after pulverization of the calcium compound becomes a cubic shape, and the permeability to concrete cracks is excellent. A pulverizer using high-pressure water is preferable.

  The high-speed stirrer preferably has a structure that not only simply rotates the stirrer at a high speed but also a so-called turbulent state and a shear force acts on the particles. For example, trade names “Sharp Flow Mill” manufactured by Taiheiyo Kiko Co., Ltd., trade names “Homomixer”, “Homomic Line Mill”, and “Homo Dispers” manufactured by Tokushu Kika Kogyo Co., Ltd. are similar. Further, the medium agitating mill is preferably pulverized using beads of 1 mm or less. As the media agitation mill for grinding using beads of 1 mm or less, the product name “Star Mill” manufactured by Ashizawa Finetech Co., Ltd., the product name “SC-Mill” manufactured by Mitsui Mining Co., Ltd., and the product name “Dual Apex Mill” manufactured by Kotobuki Industries Co., Ltd. Or the like. In addition, a pulverizer using high-pressure water applies a high pressure of 50 to 400 MPa to the slurry, branches the slurry into two flow paths, and pulverizes them by colliding against each other at a portion where they rejoin. Examples of such a crusher include Sugino Machine's product names “Starburst” and “Ultimizer”, Nanomizer's product name “Nanomizer”, and Microfluidic Corporation's product name “Microfluidizer”. . Among these, “starburst” is particularly preferable in that the dispersibility of the fine particle silica is improved, and the shape of the calcium compound after pulverization becomes a cubic shape and the permeability to cracks in the concrete is excellent.

Furthermore, a polymer dispersion is used from the viewpoints of maintaining appropriate plasticity and preventing the flow of the injection material, and preventing the compression strength of the injection material after curing from being lowered. The polymer dispersion, et styrene - using vinyl acetate copolymer or a styrene-butadiene copolymer. Among these, an ethylene-vinyl acetate copolymer is more preferable because it is effective in a small amount.
The polymer dispersion is usually blended with the A material, but when used in combination with the B material, it reacts immediately with the calcium compound and thickens. Therefore, if a predetermined viscosity is required, blend with the B material. Is also possible.

The amount of the polymer dispersion, relative to 100 parts fine particle silica material A is 0.1-10 parts in terms of solid content, 0.5 to 3 parts virtuous preferable. When the added amount exceeds 10 parts, the viscosity becomes high and the permeability to concrete cracks may be poor.

The injection material of the present invention can contain a curing time adjusting agent in order to adjust the curing time.
Although it does not specifically limit as a curing time regulator, For example, inorganic salts, such as well-known alkali metal sulfate, alkali metal carbonate, alkali metal bicarbonate, and alkali metal phosphate, gluconic acid, tartaric acid , Citric acid, malic acid, and one or more selected from organic acids such as lactic acid or salts thereof. Among these, alkali metal sulfates and / or alkali metal carbonates are preferable from the viewpoint of improving compressive strength, and alkali metal sulfates are more preferable. Examples of the alkali metal sulfate include sodium sulfate and potassium sulfate.

  The amount of the curing time adjuster used is preferably 30 parts or less, more preferably 0.1 to 30 parts, and most preferably 1 to 10 parts with respect to 100 parts of the calcium compound of the B material. If the curing time adjusting agent exceeds 30 parts, the permeability of concrete to cracks may be poor.

  The mixing ratio of the A material and the B material is preferably 5: 1 to 1: 5, and more preferably 2: 1 to 1: 2.

  In injecting the injection material of the present invention into concrete cracks, as a method of mixing the A material and the B material, a so-called double tube is used to join the A material and the B material at the tip portion and inject them. 2 shot system, both A material and B material are mixed and injected on the way from the injection pump to the injection tube, so-called 1.5 shot system, and A material or B material is mixed in a mixing tank such as a mixer. After blending, it can be performed by any method of so-called one-shot method, in which other liquids are added and mixed, and then injected as one liquid.

  The pouring method of the present invention is characterized by pouring the above-mentioned pouring material into concrete cracks. The injection method of the present invention has excellent permeability to cracks of fine concrete of, for example, 100 μm or less, and can maintain a long-term water stoppage without extruding the injection material even when a high osmotic water pressure acts. The method is related to an injection method, and the above effect can be obtained.

  Hereinafter, the present invention will be described with reference to experimental examples, but the present invention is not limited to these experimental examples. Unless otherwise specified, the experimental examples were conducted at 20 ° C.

Experimental example 1
100 parts of fine particle silica with different particle sizes and types, 5 parts of dispersant α in terms of solid content, and 100 parts of water are mixed and subjected to a wet dispersion treatment with the product name “Starburst” manufactured by Sugino Machine, and polymer dispersion. And A material (particulate silica S1-S7 in A material) was produced. On the other hand, 100 parts of commercially available calcium hydroxide (average particle size 9.5 μm), 10 parts of dispersant α in terms of solid content, and 150 parts of water are mixed, and the product name “Starburst” manufactured by Sugino Machine Co., Ltd. is also used. The pulverization time is changed and wet pulverization and dispersion treatment is performed. Further, 5 parts of a curing time adjusting agent is added to 100 parts of the calcium compound of the B material to produce the B material (calcium compounds C1 to C6 in the B material). did. The pressure applied to the starburst slurry was all 245 MPa. The A material and the B material were mixed so that the amount of the calcium compound used was 75 parts with respect to 100 parts of the fine particle silica to prepare an injection material. The hardening time of the injection material, the compressive strength of the injection material, and the penetration width for confirming the permeability to cracks in the concrete were measured. The formulation and results are shown in Table 1.
The fine-particle silica was produced by a method in which a slurry in which metal silicon powder was dispersed in water was injected into a flame at a protrusion speed of 2 to 150 m / sec, burned, oxidized, and melted into a spherical shape.

<Materials used>
Fine particle silica S1: slurry having an average particle diameter of 0.05 μm after wet dispersion treatment, a sphericity of 97%, an amorphization rate of 100%, and a concentration of metal silicon powder in which metal silicon powder is dispersed in water is 30% Fine particle spherical silica fine particle silica S2 produced by a method of injecting, burning and oxidizing at a protruding speed of 150 m / second or more: average particle size 0.1 μm after wet dispersion treatment, sphericity 97%, amorphous ratio 100%, Spherical silica fine particle silica S3 manufactured by a method in which a metal silicon powder dispersed in water and having a metal silicon powder concentration of 30% is injected into a flame at a protruding speed of 120 m / sec or more and burned and oxidized, wet dispersion A slurry having an average particle diameter of 0.8 μm after treatment, a sphericity of 97%, an amorphization rate of 100%, a metal silicon powder dispersed in water and a metal silicon powder concentration of 30% is flamed. Fine particle spherical silica fine particle silica S4 manufactured by a method of injecting, burning, and oxidizing at a protrusion speed of 100 m / second or more: average particle size 1.0 μm after wet dispersion treatment, sphericity 96%, amorphous ratio 100%, Spherical silica fine particle silica S5 produced by a method in which a metal silicon powder dispersed in water and having a metal silicon powder concentration of 30% is injected into a flame at a protruding speed of 50 m / sec or more and burned and oxidized, wet dispersion An average particle size of 3.5 μm after treatment, a sphericity of 95%, an amorphous ratio of 100%, a metal silicon powder dispersed in water with a metal silicon powder concentration of 30% in a flame is a slurry of 2 m / second or more. Fine spherical silica fine particle silica S6 produced by a method of jetting, burning and oxidizing at a protruding speed: Ferrosilicon by-product silica fume, average particle size 20 μm after wet dispersion treatment, reference , Average particle size 5.5μm in the case of ultrasonic dispersion treatment, sphericity 86%
Fine particle silica S7: Silica sol, average particle size after wet dispersion treatment of 10.1 μm, reference value, average particle size after ultrasonic dispersion treatment of 9.8 μm, sphericity of 75%
Calcium compound C1: Average particle size after wet pulverization and dispersion treatment 0.05 μm, Calcium hydroxide calcium compound C2: Average particle size after wet pulverization and dispersion treatment 0.1 μm, Calcium hydroxide calcium compound C3: After wet pulverization and dispersion treatment Average particle size 0.8 μm, calcium hydroxide calcium compound C4: average particle size 1.0 μm after wet pulverization dispersion treatment, calcium hydroxide calcium compound C5: average particle size 3.5 μm after wet pulverization dispersion treatment, reference value The average particle size when sonicated is 0.5 μm, calcium hydroxide dispersant α: naphthalene sulfonic acid dispersant, commercially available product, liquid, solid content concentration 40%
Polymer dispersion P1: Polymer dispersion made of ethylene-vinyl acetate copolymer, commercial product, solid content concentration 46%
Polymer dispersion P2: Polymer dispersion made of styrene-butadiene copolymer, commercial product, solid content concentration 45%
Curing time adjuster: Sodium sulfate, commercial water: tap water

<Evaluation method>
Average particle diameter: Laser diffraction particle size distribution meter, trade name “LA-920 type” manufactured by Horiba, Ltd. was used. The A material and the B material were measured in an aqueous medium without performing ultrasonic dispersion treatment.
Curing time: The time from when the pouring material was put into the plastic container until the fluidity disappeared even when tilted was defined as the curing time. hr is (hours), min is (minutes).
Compressive strength: A specimen of 4 × 4 × 16 cm was prepared, cured for 20 days at 20 ° C. in water, dried for 3 days at 20 ° C. and 80% relative humidity, and the compressive strength of the injected material was measured.
Penetration width: Penetration test, a 10 × 10 × 40 cm concrete specimen centered on a reinforcing bar having a diameter of 11 mm was subjected to bending load to produce a crack of 100 μm or less, and an injection material was injected. The concrete was cut after the injection material was hardened, and the penetration of the concrete into cracks was confirmed with a stereomicroscope. The minimum crack width that can be checked for injection was defined as the penetration width. The smaller the value, the better the permeability to concrete cracks.

It turns out that it is excellent in the permeability to the crack of fine concrete, and compressive strength expression by using a specific fine particle silica and a specific calcium compound.
Furthermore, it can be seen that the compressive strength of the injection material is high even when it is dried by the combined use of the polymer dispersion.

Experimental example 2
100 parts of fine particle silica S3, 5 parts of the dispersant α in terms of solid content, and 100 parts of water are mixed and subjected to a wet dispersion treatment with a product name “Starburst” manufactured by Sugino Machine Co. 3 parts of polymer dispersion P1 was added to prepare A material. On the other hand, 100 parts of calcium compound C3, 10 parts of dispersant α in terms of solid content, and 150 parts of water are mixed, and similarly, wet pulverized and dispersed with the trade name “Starburst” manufactured by Sugino Machine Co., The same procedure as in Experimental Example 1 was conducted except that the curing time adjusting agent shown in Table 2 was added to 100 parts of the calcium compound C3 to prepare a B material. The results are also shown in Table 2.

  It turns out that hardening time can be adjusted by using together a hardening time regulator.

Experimental example 3
100 parts of fine particle silica S3, a dispersant shown in Table 3 in terms of solid content, and 100 parts of water are mixed, and wet dispersion treatment is performed with a product name “Starburst” manufactured by Sugino Machine Co. 3 parts of polymer dispersion P1 was added to prepare A material. On the other hand, 100 parts of calcium compound C3, the dispersant shown in Table 3 in terms of solid content, and 150 parts of water were mixed, and similarly wet-pulverized and dispersed with the trade name “Starburst” manufactured by Sugino Machine Co. The same procedure as in Experimental Example 1 was conducted except that 5 parts of a curing time adjusting agent was added to 100 parts of the calcium compound C3 to prepare a B material. The results are also shown in Table 3.

<Materials used>
Dispersant β: Melamine sulfonic acid dispersant, commercially available product, liquid, solid concentration 40%

  It can be seen that by using a dispersant in combination with the A material and the B material, the permeability is improved and the amount of the dispersant has an optimum value.

Experimental Example 4
100 parts of fine particle silica S3, 5 parts of the dispersant α in terms of solid content, and 100 parts of water are mixed and subjected to a wet dispersion treatment with a product name “Starburst” manufactured by Sugino Machine Co. 3 parts of polymer dispersion P1 was added, and A material was produced in the same manner as in Experimental Example 1. On the other hand, 100 parts of calcium compound C3, 10 parts of dispersant α in terms of solid content, and 150 parts of water are mixed and subjected to wet pulverization and dispersion treatment under the trade name “Starburst” manufactured by Sugino Machine Co. A material B was prepared in the same manner as in Experimental Example 1 by adding 5 parts of a curing time adjusting agent to 100 parts of the compound C3. The manufactured A material and B material were mixed in the same manner as in Experimental Example 1 except that the amount of calcium compound used was mixed as shown in Table 4 with respect to 100 parts of fine particle silica S3 to prepare an injection material. It was. The results are also shown in Table 4.

  It can be seen that the compressive strength has an optimum value for the calcium compound relative to the fine-particle silica.

Experimental Example 5
100 parts of fine particle silica S3, 5 parts of the dispersant α in terms of solid content, and water shown in Table 5 are mixed, wet dispersed with a trade name “Starburst” manufactured by Sugino Machine Co., and 100 parts of fine particle silica S3 3 parts of the polymer dispersion P1 was added to the A material in the same manner as in Experimental Example 1. On the other hand, 100 parts of commercially available calcium hydroxide (average particle size 9.5 μm), 10 parts of dispersant α in terms of solid content, and water shown in Table 5 were mixed, and the product name “Starburst” manufactured by Sugino Machine Co., Ltd. Then, 5 parts of a curing time adjusting agent was added to 100 parts of the calcium compound C3 of the B material, and a B material was produced in the same manner as in Experimental Example 1. The manufactured A material and B material were mixed with 100 parts of fine particle silica S3 so that the amount of calcium compound used was 75 parts, and the same procedure as in Experimental Example 1 was performed, except that an injection material was prepared. . The results are also shown in Table 5.

  By changing the concentrations of the A and B materials, the curing time, compressive strength, and penetration width can be adjusted.

  The concrete crack repairing injection material of the present invention is used, for example, in the following applications.

This is an injection material for repairing cracks in concrete that has excellent permeability even for cracks in fine concrete of 100 μm or less, and that provides a high water-stopping effect and durability, and can be applied to any concrete structure. .
Furthermore, the injection method of the present invention can be applied not only to concrete but also to fine cracks such as mortar and bedrock.

Claims (18)

  A wet-dispersed material A containing fine particle silica having an average particle size of 1.0 μm or less, a dispersant, a polymer dispersion, and water, and a calcium compound, a dispersant, and water having an average particle size of 1.0 μm or less An injecting material for repairing cracks in concrete mixed with a B material that has been subjected to wet pulverization and dispersion treatment, wherein the concentration of the fine particle silica is 40 to 70%, and the polymer dispersion is an ethylene-vinyl acetate co-polymer. It consists of a polymer or a styrene butadiene copolymer, 0.1 to 10 parts by mass in terms of solid content, and the calcium compound has a concentration of 30 to 60% and 100 parts by mass of the fine particle silica with respect to 100 parts by mass of the fine particle silica. An injecting material for repairing cracks in concrete, characterized in that it is 50 to 100 parts by mass relative to the part. The average particle size of the fine particles of silica and the calcium compound, the concrete according to claim 1, characterized in that the average particle diameter measured using a no laser diffraction particle size distribution meter to perform ultrasonic dispersion treatment Injection material for crack repair. 3. The concrete crack repairing injection material according to claim 1, wherein the fine particle silica is fine particle spherical silica having an average value of sphericity of 95% or more. The said calcium compound is calcium hydroxide, The injection material for the crack repair of concrete of any one of Claims 1-3 characterized by the above-mentioned. The amount of dispersant in the A material, relative to particles of silica 100 parts by weight, either of claims 1-4, characterized in that from 0.1 to 30 parts by weight in terms of solid content 1 The injection material for crack repair of concrete as described in the item. The usage-amount of the dispersing agent in the said B material is 1-30 mass parts in conversion of solid content with respect to 100 mass parts of calcium compounds, The any one of Claims 1-5 characterized by the above-mentioned. Filling material for repairing cracks in concrete. Furthermore, 0.1-10 mass parts of hardening time regulators are contained with respect to 100 mass parts of said calcium compounds, The concrete of any one of Claims 1-6 characterized by the above-mentioned. Injection material for crack repair.   An ethylene-vinyl acetate copolymer having an average particle size of 1.0 μm or less and a concentration of 40 to 70% of fine particle silica and 0.1 to 10 parts by mass in terms of solid content with respect to 100 parts by mass of the fine particle silica. Alternatively, a material dispersion prepared by preparing a suspension containing a polymer dispersion made of a styrene-butadiene copolymer and water, and a wet dispersion treatment by mixing this suspension with a dispersant and, if necessary, water. On the other hand, the average particle size is 1.0 μm or less, the concentration is 30 to 60%, and contains 50 to 100 parts by mass of a calcium compound, a dispersant, and water with respect to 100 parts by mass of the fine-particle silica. A suspension B is prepared, and, if necessary, water B is mixed with the suspension as necessary to produce a B material that has been wet pulverized and dispersed, and the A material and the B material are mixed. For repairing cracks in concrete A method for producing an injection material. 9. The injection material for repairing cracks in concrete according to claim 8 , wherein the fine particle silica is manufactured by a method in which a slurry in which metal silicon powder is dispersed in water is injected into a flame and burned and oxidized. Manufacturing method. The average particle size of the fine particles of silica and the calcium compound, according to claim 8 or 9, characterized in that an average particle diameter measured using a no laser diffraction particle size distribution meter to perform ultrasonic dispersion treatment A method for producing an injection material for repairing cracks in concrete. The method for producing a concrete crack repairing injection material according to any one of claims 8 to 10 , wherein the fine particle silica is fine particle spherical silica having an average value of sphericity of 95% or more. . The method for producing an injection material for repairing cracks in concrete according to any one of claims 8 to 11 , wherein the calcium compound is calcium hydroxide. Wherein the material A and / or B material, to any one of claims 8-12, characterized in that the wet dispersion process and / or wet grinding dispersion treatment using a pulverizer using a high pressure water Method of injection material for repairing cracks in concrete. The amount of dispersant in the A material, relative to particles of silica 100 parts by weight, any of the claims 8 to 13, characterized in that from 0.1 to 30 parts by weight in terms of solid content 1 The manufacturing method of the injection material for crack crack repair of concrete as described in a term. The amount of dispersant in the B material, to calcium compound 100 parts by weight, to any one of claims 8 to 14, characterized in that 1 to 30 parts by weight in terms of solid content The manufacturing method of the injection material for crack crack repair of the described concrete. Moreover, concrete according to setting time regulating agent, to any one of claims 8 to 15, to the calcium compound 100 parts by weight, and characterized by containing 0.1 to 10 parts by weight Method of injection material for repairing cracks in steel. An injection method characterized by injecting the concrete crack repairing injection material according to any one of claims 1 to 7 . The said material A and the material B, one shot method, 1.5 shot method, and mixed by any of the methods of the two-shot method, as claimed in claim 17, characterized in that injected into cracks in concrete Injection method.