Geopolymer composition

Abstract

To provide a geopolymer composition which is used in a method for repairing a crack of a concrete structure using an injector, and can be injected in a sufficient amount to the details of the crack as compared with a conventional method.SOLUTION: A geopolymer composition according to one embodiment of the present invention is a geopolymer composition obtained by mixing an active filler containing fly ash or blast furnace slag powder with an alkaline solution, wherein the active filler has an average particle diameter of 8.20 μm or less, and a liquid-solid ratio of the alkaline solution to the active filler is 0.7 to 0.9.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a geopolymer composition for crack repair in concrete structures. [Background technology]

[0002] Conventionally, when repairing concrete structures that have developed cracks due to aging, one repair method involves injecting a geopolymer composition directly into the cracks using an injector. The geopolymer composition used in this repair method is a mixture of an alkaline solution and an active filler containing perlite powder and blast furnace slag powder (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7036315 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in such conventional geopolymer compositions, the particle sizes of the constituent components, particularly the average particle size of the active filler, are large, so repair methods using an injector such as those described above cannot inject a sufficient amount of geopolymer composition into the fine cracks, and there is a risk that sufficient repair will not be achieved. Furthermore, with conventional geopolymer compositions, the appropriate relative particle size of the active filler that would allow sufficient injection into the fine cracks was unknown. In other words, there was a need for a geopolymer composition to be used in methods for repairing cracks in concrete structures using an injector that could be injected in sufficient amounts to reach the fine cracks, compared to conventional products.

[0005] The present invention has been made in view of these problems, and one of its objects is to provide a geopolymer composition that can be injected in a sufficient amount to reach the finer details of the cracks in a geopolymer composition used in a method for repairing cracks in concrete structures using an injector. [Means for solving the problem]

[0006] The present invention has been made to solve at least some of the above-mentioned problems, and can be realized as the following application examples. Note that the reference symbols and supplementary explanations in this section indicate the correspondence with the embodiments described later to help understand the present invention, and do not limit the present invention in any way.

[0007] The geopolymer composition, which is an example of application of the present invention, is a geopolymer composition obtained by mixing an alkaline solution with an active filler containing fly ash or blast furnace slag powder, and the active filler has an average particle size of 8.20 μm or less.

[0008] In the geopolymer composition of the above-mentioned application example, the active filler may have a relative particle amount of particles having a particle size of 10.00 μm or less relative to all particles of 55% or more. Furthermore, in the geopolymer composition of the above-mentioned application example, the active filler may have a relative particle amount of particles having a particle size of 5.00 μm or less relative to all particles of 39% or more. Furthermore, in the geopolymer composition of the above-mentioned application example, the active filler may have a relative particle amount of particles having a particle size of 1.00 μm or less relative to all particles of 9% or more. Furthermore, in the geopolymer composition of the above-mentioned application example, the liquid-solid ratio of the alkaline solution to the active filler may be 0.7 to 0.9. [Brief explanation of the drawings]

[0009] [Figure 1-1] FIG. 3 is a diagram illustrating the particle size distribution of a first active filler. [Figure 1-2] FIG. 4 is a diagram illustrating the particle size distribution of a second active filler. [Figure 1-3] FIG. 4 is a diagram illustrating the particle size distribution of a third active filler. [Figure 1-4] FIG. 4 is a diagram illustrating the particle size distribution of a fourth active filler. [Figure 1-5] FIG. 10 is a diagram illustrating the particle size distribution of a fifth active filler. [Figure 1-6] FIG. 4 is a diagram illustrating the particle size distribution of a sixth active filler. [Figure 1-7] FIG. 10 is a diagram illustrating the particle size distribution of a seventh active filler. [Figure 1-8] FIG. 10 is a diagram illustrating the particle size distribution of the eighth active filler. [Figure 1-9] FIG. 10 is a diagram illustrating the particle size distribution of the ninth active filler. [Figure 1-10] FIG. 10 is a diagram illustrating the particle size distribution of the tenth active filler. [Figure 2] FIG. 10A is a diagram illustrating the relationship between the grinding time, average particle size, relative particle amount of particles with a particle size of 10.00 μm or less, relative particle amount of particles with a particle size of 5.00 μm or less, and relative particle amount of particles with a particle size of 1.00 μm or less for each of the first to tenth active fillers; and FIG. 10B is a diagram illustrating the relationship between the distribution of particles of each particle size and relative particle amount for each of the first to tenth active fillers. [Figure 3] (A) is a schematic diagram for explaining the outline of the jig used in the injection experiment, and (B) is a diagram showing the results of an injection experiment using 30 types of injection materials, with the liquid-solid ratios of the first to tenth injection materials being three types: 0.7, 0.8, and 0.9. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments to which the present invention is applied will be described with reference to the drawings. Note that the embodiments of the present invention are not limited to the following embodiments, and various forms may be adopted as long as they fall within the technical scope of the present invention.

[0011] <Geopolymer composition description> One embodiment of the present invention is a geopolymer composition comprising an alkaline solution mixed with an activated filler, such as fly ash or blast furnace slag powder. The liquid-solid ratio (W / P: alkaline solution / activated filler) of the geopolymer composition is preferably 0.7 to 0.9. A liquid-solid ratio of less than 0.7 is difficult to mix, and the initial viscosity is high, making injection difficult. A liquid-solid ratio greater than 0.9 increases the risk of bleeding.

[0012] The alkaline solution in the geopolymer composition of this embodiment is a mixture of the following potassium silicate aqueous solution and sodium hydroxide aqueous solution in a weight ratio of 9:1. Potassium silicate aqueous solution (SiO2: 21.0%, K2O: 9.3%, specific gravity: 1.269) Sodium hydroxide solution (molarity: 10.0 mol / L, specific gravity: 1.33)

[0013] The active filler in the geopolymer composition of this embodiment is a mixture of fly ash, blast furnace slag powder, and metakaolin in a weight ratio of 8:1:1, as shown below, which is pulverized to an average particle size of 8.20 μm or less. The pulverization method for this mixture involves placing 50 kg of the mixture in a dry ball mill (manufactured by Ishizaki Iron Works, Ltd.: 500 L, 60 Hz, 38 rpm) and operating it for a predetermined time until the average particle size is 8.20 μm or less. Details will be described later. The pulverization method for this mixture is not limited to the method using the dry ball mill described above, but may also be a method using various dry pulverizers (jet mill, cyclone mill, roller mill, planetary mill, etc.). Fly ash JIS Class 1 (FA) (density: 2.36 g / cm 3 , specific surface area: 5327cm 2 / g) Blast furnace slag powder JIS8000 grade (BFS8) (density: 2.90 g / cm 3 , Specific surface area: 8500cm 2 / g) Metakaolin (average particle size: 3.00 μm)

[0014] <Explanation of particle size distribution of various active fillers> The particle size distributions of ten types of active fillers, the first active filler to the tenth active filler, will be described with reference to Figures 1-1 to 1-10 and Figure 2. The first active filler to the tenth active filler are mixtures of the materials described above, and the operating time of the dry ball mill used for pulverization (hereinafter referred to as the pulverization time) was varied for each active filler. Furthermore, the particle size distribution was measured using a laser diffraction particle size analyzer (SALD-300V, manufactured by Shimadzu Corporation) for a predetermined amount of sample of each active filler. Figure 1-1 is a diagram illustrating the particle size distribution of the first active filler, Figure 1-2 is a diagram illustrating the particle size distribution of the second active filler, Figure 1-3 is a diagram illustrating the particle size distribution of the third active filler, Figure 1-4 is a diagram illustrating the particle size distribution of the fourth active filler, and Figure 1-5 is a diagram illustrating the particle size distribution of the fifth active filler. 1-6 is a diagram illustrating the particle size distribution of the sixth active filler, 1-7 is a diagram illustrating the particle size distribution of the seventh active filler, 1-8 is a diagram illustrating the particle size distribution of the eighth active filler, 1-9 is a diagram illustrating the particle size distribution of the ninth active filler, and 1-10 is a diagram illustrating the particle size distribution of the tenth active filler. Fig. 2(A) is a diagram illustrating the relationship between the grinding time, average particle size, relative particle amount of particles having a particle size of 10.00 μm or less, relative particle amount of particles having a particle size of 5.00 μm or less, and relative particle amount of particles having a particle size of 1.00 μm or less for each of the first to tenth active fillers. Fig. 2(B) is a diagram illustrating the relationship between the particle distribution of each particle size and the relative particle amount for each of the first to tenth active fillers.

[0015] As shown in Figure 1-1, when the first active filler is milled for 0.25 hours (15 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 33.439%, the relative particle amount of particles with a particle size of 5.00 μm or less is 19.906%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 2.504%. The average particle size of the first active filler is 15.271 μm.

[0016] As shown in Figure 1-2, when the second active filler is milled for 0.5 hours (30 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 36.848%, the relative particle amount of particles with a particle size of 5.00 μm or less is 23.047%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 3.403%. The average particle size of the second active filler is 14.032 μm.

[0017] As shown in Figure 1-3, the third active filler has a particle size distribution in which, by grinding for 1 hour (60 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 38.853%, the relative particle amount of particles with a particle size of 5.00 μm or less is 24.954%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 4.564%. The average particle size of the third active filler is 13.444 μm.

[0018] As shown in Figure 1-4, the fourth active filler has a particle size distribution in which, by grinding for 2 hours (120 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 44.463%, the relative particle amount of particles with a particle size of 5.00 μm or less is 29.607%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 5.934%. The average particle size of the fourth active filler is 11.671 μm.

[0019] As shown in Figure 1-5, the fifth active filler has a particle size distribution in which, by grinding for 3 hours (180 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 55.392%, the relative particle amount of particles with a particle size of 5.00 μm or less is 39.560%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 9.589%. The average particle size of the fifth active filler is 8.156 μm.

[0020] As shown in Figure 1-6, the sixth active filler has a particle size distribution in which, by grinding for 4 hours (240 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 62.385%, the relative particle amount of particles with a particle size of 5.00 μm or less is 46.345%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 14.029%. The average particle size of the sixth active filler is 5.821 μm.

[0021] As shown in Figure 1-7, the seventh active filler has a particle size distribution in which, by grinding for 6 hours (360 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 68.499%, the relative particle amount of particles with a particle size of 5.00 μm or less is 52.440%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 16.315%. The average particle size of the seventh active filler is 4.560 μm.

[0022] As shown in Figure 1-8, the eighth active filler has a particle size distribution in which, by grinding for 8 hours (480 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 78.175%, the relative particle amount of particles with a particle size of 5.00 μm or less is 60.486%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 19.860%. The average particle size of the eighth active filler is 3.449 μm.

[0023] As shown in Figure 1-9, the ninth active filler has a particle size distribution in which, by grinding for 10 hours (600 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 84.075%, the relative particle amount of particles with a particle size of 5.00 μm or less is 66.052%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 22.132%. The average particle size of the ninth active filler is 2.969 μm.

[0024] As shown in Figure 1-10, the 10th active filler has a particle size distribution in which, by grinding for 12 hours (720 minutes), the relative particle amount of particles with a particle size of 10.00 μm or less is 88.064%, the relative particle amount of particles with a particle size of 5.00 μm or less is 69.239%, and the relative particle amount of particles with a particle size of 1.00 μm or less is 23.108%. The average particle size of the 10th active filler is 2.639 μm.

[0025] 2(A) and (B), the six active fillers (No. 5 to No. 10 active fillers) have a longer grinding time than the four active fillers (No. 1 to No. 4 active fillers), and therefore have a larger relative particle amount of particles with a relatively smaller particle size of 10.00 μm or less than the four active fillers (No. 1 to No. 4 active fillers). Specifically, the six active fillers (No. 5 to No. 10 active fillers) have a relative particle amount of 55% to 89% of particles with a particle size of 10.00 μm or less, a relative particle amount of 39% to 70% of particles with a particle size of 5.00 μm or less, and a relative particle amount of 9% to 24% of particles with a particle size of 1.00 μm or less. In addition, the six types of active fillers, the 5th active filler to the 10th active filler, have relatively smaller particle diameters than the four types of active fillers, the 1st active filler to the 4th active filler, so their average particle diameters are 8.20 μm or less and 2.60 μm or more.

[0026] <Explanation of injection experiment using injection material (geopolymer composition)> The results of an injection experiment using ten types of geopolymer compositions, the first injection material to the tenth injection material, are described below with reference to Figure 3. Figure 3(A) is a schematic diagram illustrating the outline of the jig used in the injection experiment, and Figure 3(B) shows the results of an injection experiment using 30 types of injection materials, each with three liquid-solid ratios of 0.7, 0.8, and 0.9 for the first injection material to the tenth injection material.

[0027] Here, we will specifically explain the injection experiment of the first injection material to the tenth injection material, which is a geopolymer composition. First, the first injection material to the tenth injection material used in this injection experiment are obtained by mixing the first active filler to the tenth active filler with the alkaline solution described above, the first injection material is mixed with the first active filler, the second injection material is mixed with the second active filler, the third injection material is mixed with the third active filler, the fourth injection material is mixed with the fourth active filler, the fifth injection material is mixed with the fifth active filler, the sixth injection material is mixed with the sixth active filler, the seventh injection material is mixed with the seventh active filler, the eighth injection material is mixed with the eighth active filler, the ninth injection material is mixed with the ninth active filler, and the tenth injection material is mixed with the tenth active filler. In this injection experiment, a total of 30 types of injection materials were used, with the liquid-solid ratio (W / P) of each of the first to tenth injection materials set to 0.7, 0.8, and 0.9. The experiment measured the reach distance l (mm) of the injection material injected into a gap in an injection experiment jig 10, which had a gap simulating a 0.1 mm wide crack in a concrete structure. This experiment was conducted three times for each of the 30 types of injection materials. Then, based on the average reach distance measured in the three injection experiments for each injection material, the "injection reach (average reach distance l (mm) of each injection material / maximum distance L (mm) of the gap x 100) (%)" (see Figure 3(A)) for each of the 30 types of injection materials was calculated, and a score of 80% or higher was considered pass (◯: 80% or higher but less than 90%, ◎: 90% or higher).

[0028] As shown in Figure 3(A), the jig 10 used in the injection experiment consisted of two acrylic plates 12a and 12b, each 300 mm long, 300 mm wide, and 15 mm thick, and a 0.1 mm-thick spacer 13 made of a Teflon® sheet. The jig 10 consisted of two acrylic plates 12a and 12b stacked together with a predetermined spacer 13 sandwiched between them. The plates were secured in place with multiple clamps (not shown) to ensure that no gaps were formed between the acrylic plates 12a and 12b and the spacer 13, while a 0.1 mm gap was formed between the two acrylic plates 12a and 12b. An injection port 15 was formed to allow injection of the injection material into the 0.1 mm gap using a spring-loaded automatic injection injector (not shown). The maximum distance L (mm) of the 0.1 mm gap in the jig 10 was 300 mm. In addition, while typical injection experiments are conducted into a gap of 0.2 mm as a pseudo-crack, the injection experiment in this embodiment was conducted into a gap of 0.1 mm as a pseudo-crack, which is a more severe condition.

[0029] As shown in Figure 3(B), for the first grout, the one with a liquid-solid ratio (W / P) of 0.7 is rejected (×) because the grouting degree is 7%, the one with a liquid-solid ratio (W / P) of 0.8 is rejected (×) because the grouting degree is 17%, and the one with a liquid-solid ratio (W / P) of 0.9 is rejected (×) because the grouting degree is 10%. For the second grout, the one with a liquid-solid ratio (W / P) of 0.7 is rejected (×) because the grouting degree is 23%, the one with a liquid-solid ratio (W / P) of 0.8 is rejected (×) because the grouting degree is 43%, and the one with a liquid-solid ratio (W / P) of 0.9 is rejected (×) because the grouting degree is 47%. For the third grout, the one with a liquid-solid ratio (W / P) of 0.7 failed (×) because the grouting degree was 27%, the one with a liquid-solid ratio (W / P) of 0.8 failed (×) because the grouting degree was 50%, and the one with a liquid-solid ratio (W / P) of 0.9 failed (×) because the grouting degree was 47%.For the fourth grout, the one with a liquid-solid ratio (W / P) of 0.7 failed (×) because the grouting degree was 42%, the one with a liquid-solid ratio (W / P) of 0.8 failed (×) because the grouting degree was 67%, and the one with a liquid-solid ratio (W / P) of 0.9 failed (×) because the grouting degree was 50%.

[0030] As shown in Figure 3(B), for the fifth grouting material, the one with a liquid-solid ratio (W / P) of 0.7 has a grouting reach of 83%, which is a pass (◯), the one with a liquid-solid ratio (W / P) of 0.8 has a grouting reach of 93%, which is a pass (◎), and the one with a liquid-solid ratio (W / P) of 0.9 has a grouting reach of 90%, which is a pass (◎).For the sixth grouting material, the one with a liquid-solid ratio (W / P) of 0.7 has a grouting reach of 93%, which is a pass (◎), the one with a liquid-solid ratio (W / P) of 0.8 has a grouting reach of 100%, which is a pass (◎), and the one with a liquid-solid ratio (W / P) of 0.9 has a grouting reach of 100%, which is a pass (◎). For the seventh injection material, the one with a liquid-solid ratio (W / P) of 0.7 has an injection reach of 100% and is therefore passed (◎), the one with a liquid-solid ratio (W / P) of 0.8 has an injection reach of 100% and is therefore passed (◎), and the one with a liquid-solid ratio (W / P) of 0.9 has an injection reach of 100% and is therefore passed (◎).

[0031] As shown in Figure 3(B), for the eighth grouting material, the one with a liquid-solid ratio (W / P) of 0.7 is passed (◎) because the grouting reach is 100%, the one with a liquid-solid ratio (W / P) of 0.8 is passed (◎) because the grouting reach is 100%, and the one with a liquid-solid ratio (W / P) of 0.9 is passed (◎) because the grouting reach is 100%. For the ninth grouting material, the one with a liquid-solid ratio (W / P) of 0.7 is passed (◎) because the grouting reach is 100%, the one with a liquid-solid ratio (W / P) of 0.8 is passed (◎) because the grouting reach is 100%, and the one with a liquid-solid ratio (W / P) of 0.9 is passed (◎) because the grouting reach is 100%. For the 10th injection material, the one with a liquid-solid ratio (W / P) of 0.7 has an injection reach of 100% and is therefore passed (◎), the one with a liquid-solid ratio (W / P) of 0.8 has an injection reach of 100% and is therefore passed (◎), and the one with a liquid-solid ratio (W / P) of 0.9 has an injection reach of 100% and is therefore passed (◎).

[0032] As described above, the fifth to tenth injection materials, which are geopolymer compositions containing fifth to tenth active fillers with average particle sizes of 8.20 μm or less and 2.60 μm or more, passed the injection test. On the other hand, the first to fourth injection materials, which are geopolymer compositions containing first to fourth active fillers with average particle sizes greater than 8.20 μm, failed the injection test. Furthermore, the fifth to tenth injection materials, which are geopolymer compositions containing fifth to tenth active fillers with a relative particle size of 10.00 μm or less (55% or more), a relative particle size of 5.00 μm or less (39% or more), and a relative particle size of 1.00 μm or less (9% or more), passed the injection test. On the other hand, the first to fourth injection materials, which are geopolymer compositions each composed of a first active filler to a fourth active filler in which the relative particle amount of particles having a particle diameter of 10.00 μm or less is less than 45%, the relative particle amount of particles having a particle diameter of 5.00 μm or less is less than 30%, and the relative particle amount of particles having a particle diameter of 1.00 μm or less is less than 6%, failed the injection experiment. Note that the six types of injection materials, the fifth to tenth injection materials, correspond to the geopolymer composition of the present embodiment described above.

[0033] <Characteristics of the geopolymer composition of this embodiment> The fifth to tenth injection materials, which are geopolymer compositions of the above-mentioned embodiment, are geopolymer compositions obtained by mixing an alkaline solution with an active filler containing fly ash or blast furnace slag powder, and the fifth to tenth active fillers, which are active fillers, are characterized in that they have an average particle size of 8.20 μm or less.

[0034] According to this geopolymer composition, the fifth to tenth grouting materials in the above-mentioned embodiment, the fifth to tenth active fillers, which are the mixed active fillers, have an average particle size of 8.20 μm or less, which is sufficiently small that a sufficient amount can be injected into a gap simulating a 0.1 mm wide crack in a concrete structure, and the injection experiment can be passed. Therefore, with this geopolymer composition, in a method of repairing cracks in a concrete structure using an injector, a sufficient amount can be injected into the cracks in detail more than conventional methods.

[0035] Furthermore, in the fifth to tenth injection materials, which are geopolymer compositions of the above-described embodiment, the fifth to tenth active fillers, which are active fillers, are characterized by a relative particle amount of particles with a particle diameter of 10.00 μm or less, of 55% or more relative to the total particle amount. According to such geopolymer compositions, the fifth to tenth injection materials of the above-described embodiment, which are active fillers, have a sufficiently high relative particle amount of very small particles with a particle diameter of 10.00 μm or less, at 55% or more. Therefore, sufficient amounts can be injected into gaps simulating 0.1 mm wide cracks in concrete structures, and injection experiments can be passed. Therefore, such geopolymer compositions can be injected in sufficient amounts to reach the finer details of cracks in concrete structures using an injector, compared to conventional methods. Furthermore, based on this injection experiment, it was found that in the active filler of geopolymer composition, which can be injected in sufficient quantities into the details of cracks using general repair methods, the relative particle amount of particles with a particle size of 10.00 μm or less is 55% or more.

[0036] Furthermore, in the fifth to tenth injection materials, which are geopolymer compositions of the above-described embodiment, the fifth to tenth active fillers, which are active fillers, are characterized by a relative particle amount of particles with a particle size of 5.00 μm or less, of 39% or more relative to the total particle size. According to such geopolymer compositions, the fifth to tenth injection materials of the above-described embodiment, which are active fillers, have a sufficiently high relative particle amount of very small particles with a particle size of 5.00 μm or less, at 39% or more, so that a sufficient amount can be injected into a gap simulating a 0.1 mm wide crack in a concrete structure, and the injection experiment can be passed. Therefore, with such geopolymer compositions, it is possible to inject a sufficient amount into the crack's finer details in a method for repairing cracks in a concrete structure using an injector, compared to conventional methods. Furthermore, based on this injection experiment, it was found that in the active filler of geopolymer composition, which can be injected in sufficient quantities into the details of cracks using general repair methods, the relative particle amount of particles with a particle size of 5.00 μm or less is 39% or more.

[0037] Furthermore, in the fifth to tenth injection materials, which are geopolymer compositions of the above-described embodiment, the fifth to tenth active fillers, which are active fillers, are characterized by a relative particle amount of particles with a particle size of 1.00 μm or less, of 9% or more relative to the total particle size. According to such geopolymer compositions, the fifth to tenth injection materials of the above-described embodiment, which are active fillers, have a sufficiently high relative particle amount of very small particles with a particle size of 1.00 μm or less, at 9% or more, so that a sufficient amount can be injected into a gap simulating a 0.1 mm wide crack in a concrete structure, and the injection experiment can be passed. Therefore, with such geopolymer compositions, it is possible to inject a sufficient amount into the crack's finer details than conventional methods for repairing cracks in concrete structures using an injector. Furthermore, based on this injection experiment, it was found that in the active filler of geopolymer composition, which can be injected in sufficient quantities into the details of cracks using general repair methods, the relative particle amount of particles with a particle size of 1.00 μm or less is 9% or more.

[0038] Furthermore, the fifth to tenth injection materials, which are geopolymer compositions of the above-mentioned embodiment, are characterized by a liquid-solid ratio of the alkaline solution to the active filler of 0.7 to 0.9. Such geopolymer compositions do not have problems such as difficulty in mixing, difficulty in injection using a syringe due to high initial viscosity, or a tendency for bleeding to occur. Therefore, in a method for repairing cracks in concrete structures using a syringe, it is possible to inject a sufficient amount of the composition to the finer details of the cracks than conventional methods.

[0039] <Other embodiments> In the geopolymer composition of the above embodiment, the alkaline solution is a mixture of potassium silicate aqueous solution and sodium hydroxide aqueous solution, but it is not limited to this, and the aqueous solution used as the alkaline solution may be one commonly used in geopolymer compositions. For example, it may be at least one of water glass aqueous solution, sodium metasilicate aqueous solution, lithium silicate aqueous solution, potassium hydroxide aqueous solution, and lithium hydroxide aqueous solution, and may also be a mixture of each mixed in a predetermined volume ratio, a mixture of each mixed in a predetermined weight ratio, or a mixture of each mixed in a predetermined concentration.

[0040] In the geopolymer composition of the above embodiment, the active filler is a mixture of fly ash, blast furnace slag powder, and metakaolin, but is not limited thereto and may include various substances. For example, at least one of amorphous materials such as blast furnace slag powder (JIS 6000 class, JIS 4000 class), fly ash (JIS type 2), silica fume, sewage sludge incineration ash, municipal waste incineration ash molten slag powder, rice husk charcoal, and perlite powder may be included.

[0041] Furthermore, although the geopolymer composition of the above embodiment is a mixture of an alkaline solution and an active filler, this is not limited thereto, and at least one of a retarder (main component: sodium L-tartrate) and an ether-based shrinkage reducer may be added to extend the usable life of the geopolymer composition.

[0042] The present invention has been described above based on the embodiments and modifications, but the above-described embodiments of the invention are intended to facilitate understanding of the present invention and are not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit and scope of the claims, and the present invention includes equivalents thereof. [Explanation of symbols]

[0043] 10...Jig for injection experiment, 12a, 12b...Acrylic plates, 13...Spacer part, 15...Injection port.

Claims

1. A geopolymer composition comprising an alkaline solution mixed with an active filler containing fly ash or blast furnace slag powder, The active filler is a geopolymer composition characterized in that it has an average particle size of 8.20 μm or less.

2. 2. The geopolymer composition of claim 1, The active filler is characterized in that the relative particle amount of particles having a particle diameter of 10.00 μm or less is 55% or more relative to all particles.

3. 2. The geopolymer composition of claim 1, The active filler is characterized in that the relative particle amount of particles having a particle diameter of 5.00 μm or less is 39% or more relative to all particles.

4. 2. The geopolymer composition of claim 1, The active filler is characterized in that the relative particle amount of particles having a particle diameter of 1.00 μm or less is 9% or more relative to all particles.

5. 2. The geopolymer composition of claim 1, A geopolymer composition characterized in that the liquid-solid ratio of the alkaline solution to the active filler is 0.7 to 0.9.

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