KR101222212B1 - Composition for concrete using bottom ash and manufacturing method thereof - Google Patents

Abstract

PURPOSE: A concrete composition in which bottom ash is used as main aggregate is provided to enhance physical property of concrete by optimizing the ratio of water to cement. CONSTITUTION: A concrete composition in which bottom ash is used as main aggregate comprises 65-85 wt% of non-classified bottom ash, and 15-35 weight% of cement based on the unit weight 1m^3 of concrete mixture. The cement is wet-mixed with mixed water at a mixing ratio of 40-60 weight%. The mixed water includes 1-30 wt% of polymer resin emulsifier based on the water weight. One or more metakaolin, silica fume, or calcium carbonate is mixed with the cement at the weight ratio of 1:99-25:75. [Reference numerals] (AA) Remaining amount on a sieve(%); (BB) Particle size(mm)

Description

Composition for concrete using bottom ash as a main aggregate and manufacturing method thereof

The present invention relates to a polymer concrete composition using a bottom ash, which is a kind of coal ash discharged from a coal-fired power plant or an incinerator, as a main aggregate, and a method of manufacturing the same.

In general, ash (ash) is a residual mineral remaining after the organic combustible component of coal is burned. Most of the ash is generated from coal-fired power plants, as well as from waste incinerators, cogeneration plants and other industrial sites. Ash is an inorganic material (eg SiO ₂ , Al ₂ O ₃ , Fe ₂ O ₃ ), which is a recyclable material in that it is a residue of a combustion product. However, due to the combustion process, it is a problem for technical applications that the unburnt carbon is always contained incidentally.

The coal ash is classified into two types according to the particle size. When the particle size is 100 μm or less, fly ash (fly ash) is treated and when it is larger, it is treated as bottom ash (botton ash, floor ash or low ash). Fly ash is light and dispersed in the fly, and is collected by the dust collector together with the combustion gas, bottom ash is heavy and falls to the bottom of the furnace. Since these coal ashes are collected at different locations in the combustion facility, physical properties such as sintered state, density, and particle size are different. In addition, the quality of fly ash is improved with the improvement of power generation facilities, and now more than 90% is recycled as the admixture of concrete and cement raw material.

On the other hand, the bottom ash solidified by the coolant by falling into the lower part of the boiler in the state in which particles are formed by sintering in the combustion furnace is crushed to a particle size of 25 mm or less using a grinder for transport to the landfill. In general, the bottom ash crushed by the pulverizer has a particle size range of about 1 to 10 mm, and about 10 to 15% of the total ash generated. The bottom ash was mainly landfilled at the coal ash treatment plant (company head) installed in the power plant.In the past, when the land utilization rate was high, the ash ash was rather easy, but the rapid increase in factory site and land value due to the recent high economic growth rate. As a result, it is relatively difficult to find a company leader who needs three to four times the size of a plant.

At the point where environmental preservation and recycling of resources are emphasized, this study is a case study of bottom ash at home and abroad. Currently, research on bottom ash is being actively conducted, such as concrete development, water treatment using high carbon coal ash, and agricultural use of coal ash. In addition, examples of using the bottom ash as an aggregate is to replace a part of the natural and artificial aggregate (Korean Patent Publication No. 1997-074706), or to use a part of the bottom ash of the thermal power plant in the manufacture of lightweight building materials (Korea Patent Publication No. 1997-061815) and fly ash, gypsum, calcium carbonate and lime mixed with extruded at high pressure to produce a brick product (U.S. Patent No. 5,358,760).

However, most of the bottom ash is of low quality as aggregate, except that it is used as a small amount of subgrade soils near the power plant. Most of the bottom ash is simply landfilled at the company site around the power plant or mixed with fly ash inland or coastal landfill. Therefore, as well as the difficulty of securing the ash processing site, the treatment of the bottom ash causing the problem of environmental pollution has become a problem.

On the other hand, in recent years, many researchers are interested in the development of technology for producing high-strength concrete using bottom ash, in particular, Korean Patent Publication Nos. 2005-0001983 and 2005-0082083 produce high-strength concrete using bottom ash Although the contents of the disclosure are disclosed in the literature, the techniques disclosed in these documents do not use the bottom ash as it is without pretreatment, but use a separate bottom ash, which requires a separate process, and a method for producing a concrete on a large scale is required. It is not disclosed.

In addition, according to the currently known technology, there are many difficulties in producing a product having all the same physical properties, such as compressive strength, using only the bottom ash as aggregate, especially the bottom ash embedded in the landfill of thermal power plants This is because there are limitations in applying the bottom ash to the aggregate of concrete that uses a large amount of ash, such as the size of the fine powder is different and the water content is 18-35% and the unspecified water content.

Therefore, if a technology for producing high-strength concrete by using bottom ash in concrete production without special pretreatment is developed, it may induce a great economic effect in the construction industry.

Therefore, the present inventors, in order to solve the above problems, when using the bottom ash as waste as the main aggregate, having a strength equal to or greater than that when using a common common material, it can produce a concrete composition excellent in compressive strength The present invention has been completed by establishing optimum conditions.

Therefore, an object of the present invention, based on the unit weight of 1m ³ of concrete mixture, 65-85% by weight of no-class bottom ash and 15-35% by weight of cement, the cement is a polymer resin emulsifier 1 ~ 30 compared to the weight of water It is to provide a concrete composition using the bottom ash as a main aggregate, characterized in that the mixing ratio of water / cement to the mixed water added by weight% is wet mixed at 40 to 60% by weight.

In addition, another object of the present invention is to mix the 65 to 85% by weight of the unclassified bottom ash and 15 to 35% by weight of cement based on the unit weight of 1m ³ of concrete mixture with water to which the polymer resin emulsifier is added, and then hardening It is to provide a method for producing a concrete composition using the bottom ash containing the main aggregate.

In order to achieve the above object, the present invention, based on the unit weight of 1m ³ of concrete mixture, 65-85% by weight of no-class bottom ash and 15-35% by weight of cement, the cement is a polymer resin emulsifier water weight It provides a concrete composition using the bottom ash as a main aggregate, characterized in that the mixing ratio of water / cement to the mixed water added in 1 ~ 30% by weight compared to 40 ~ 60% by weight.

In one embodiment of the present invention, the unclassified bottom ash may be added by replacing up to 30 to 50% by weight with recycled aggregate or crushed aggregate.

In one embodiment of the present invention, one or more of the metakaolin, silica fume or calcium carbonate can be substituted by 1 to 25% by weight based on the weight of the cement to reduce the amount of cement used.

In one embodiment of the present invention, the polymer resin emulsifier is previously added to one or more selected from the group consisting of polyacrylic emulsifier, styrene butadiene latex emulsifier and vinyl acetate-based emulsifier in water and dissolved to be cured together during cement curing Can be.

In one embodiment of the present invention, the polymer resin emulsifier may contain at least 40% by weight solids relative to the total weight of the emulsifier.

In addition, the present invention comprises the step of mixing the 65 to 85% by weight of the bottom ash and 15 to 35% by weight of cement based on the unit weight of 1m ³ of the concrete mixture with water to which the polymer resin emulsifier is added, followed by curing. It provides a method for producing a concrete composition using the bottom ash as a main aggregate.

In one embodiment of the present invention, the polymer resin emulsifier may be added in 1 to 30% by weight based on the weight of water.

In one embodiment of the present invention, the polymer resin emulsifier may be selected from the group consisting of polyacrylic emulsifiers, styrene butadiene latex emulsifiers and vinyl acetate-based emulsifiers.

The concrete composition using the bottom ash according to the present invention as a main aggregate and a method of manufacturing the same have the effect of recycling the waste by using the bottom ash, which is finely divided in the ash treatment plant of the coal-fired power plant, in the production of concrete. Since it is used as an aggregate, there is an effect that can replace the natural aggregate that is depleted.

In addition, the method according to the present invention can improve the physical properties of the concrete by optimizing the ratio of water and cement during the production of concrete, there is an effect that can provide a concrete product having a color and physical properties that meet the needs of the concrete's consumer. .

In addition, it is possible to improve the workability and compressive strength by using a polymer emulsifier mixed with water in advance when manufacturing the concrete composition of the present invention, it is possible to shorten the concrete solidification time can improve the economics and efficiency in the construction industry have.

Figure 1 shows the particle size distribution of the bottom ash fine aggregate used in the present invention, it shows that the fine powder of 1mm or less is particularly contained compared to natural sand.

The present invention relates to a concrete composition using the bottom ash as a main aggregate and a method for manufacturing the same, and more specifically, having a strength equal to or greater than that of a concrete using a general aggregate, and having a finely divided bottom ash to prepare concrete. It is used as aggregate without the particle size classification of, based on the unit weight of 1m ³ of concrete mixture, 65 to 85% by weight of no-class bottom ash and 15 to 35% by weight of cement, the cement is a polymer resin emulsifier water It is characterized by providing a concrete composition using the bottom ash as a main aggregate, characterized in that the mixing ratio of water / cement in the mixed water added to 1 to 30% by weight relative to the weight is wet mixed at 40 to 60% by weight.

Aggregates used in the construction industry, natural or masonry aggregates, are incurred a lot of costs to secure materials, and the resources of the aggregates are gradually being exhausted. Therefore, it is urgent to develop new aggregates to replace them.

In addition, the recent structure of the structure is gradually increasing in size and ultra-high rise, thereby causing a problem such as ground subsidence due to the large load of the structure is trying to make the structure itself as lightweight as possible. Bottom ash has a structure similar to sand because the particles are formed by rapid cooling or artificial crushing after collection, and also has a structural feature that the structure can be made lightweight due to porous particles. From this point of view, if bottom ash is used as an aggregate substitute for concrete, its value is expected to be very high.

Accordingly, the present inventors have devised a method that can be used to produce a bottom ash (bottom ash) that is attached to the furnace wall, superheater and preheater in the ash generated after burning the coal in the coal power plant to fall on the floor by its own weight.

In the case of the conventional methods used to utilize the bottom ash in the concrete manufacturing, the particle size distribution of the bottom ash was used to adjust, therefore, there is a problem that additional costs are generated due to such pretreatment, especially the bottom ash embedded in the landfill In the transfer process, the size of the ash is varied and the water content is 18-35%, which has an unspecified water content. Therefore, there is a limit to using the bottom ash on a large scale.

On the other hand, the bottom ash used in the manufacture of concrete according to the present invention has the feature that it can be used for the manufacture of concrete without the separate pre-treatment process such as classification treatment, using the unclassified bottom ash itself as the main aggregate Also established a manufacturing process that can be excellent in the physical properties of concrete.

In other words, the use of polymerless emulsifiers together with concrete resin emulsifiers for concrete reinforcement to increase the strength that can be reduced due to the high content of fine particles in the bottom ash, thereby improving the compressive strength and workability by enhancing the bonding strength It can reduce the solidification time of concrete.

Thus the concrete composition using bottom ash provided by the present invention as a main aggregate may comprise, based on the unit weight of the concrete mixture 1m ^3, the non-classifying bottom ash with 65 to 85% by weight, the cement also of concrete mixtures 1m ³ It may be included in an amount of 15 to 35% by weight based on the unit weight.

The unclassified bottom ash which can be used in the present invention refers to a natural ash having an unspecified particle size distribution, that is, a bottom ash which is not subjected to an artificial treatment process, and may be used as a main aggregate for producing a concrete composition of the present invention.

On the other hand, in order for the bottom ash to be used as an aggregate for concrete, it must have appropriate weight according to the appropriate hardness and use, must not be physically and chemically harmful, its shape should be close to a cube or a circle, and the bonding paste and adhesive strength should be large. General characteristics required for aggregates, such as clean, clean and free of harmful substances.

Therefore, in order to determine whether the bottom ash used in the present invention can be utilized as aggregate, the physical and chemical properties of concrete aggregates and admixtures including bottom ash were investigated.

As a result of the investigation, the particle size distribution of the bottom ash, which is a general waste generated in thermal power plants, was found to be suitable for construction materials. However, when compared with the upper and lower particle size distribution of natural sand for general concrete, Compared with the general natural sand (sand), in particular, there are too many fine particles of less than 1mm it can be seen that a specific design for concrete mixing is required (see Fig. 1).

In addition, the main chemicals of bottom ash include silica (SiO ₂ ), alumina (Al ₂ O ₃ ), iron oxide (Fe ₂ O ₃ ), calcium oxide (CaO), magnesium oxide (MgO), sodium oxide (Na ₂ O ), Potassium oxide (K ₂ O), and the like. Among them, the content of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) accounted for more than 80% of the bottom ash chemicals. In addition, calcium oxide (CaO) and iron oxide (Fe ₂ O ₃ ) were also found. It appeared to contain a lot. In addition, it was found that the chemical composition of bottom ash did not contain harmful components in concrete, and showed very similar results to fly ash. These results indicate that the main component of the bottom ash is mainly composed of silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) as well as fly ash together with the unburnt coal powder containing 12 to 18% by weight.

In one embodiment of the present invention, the results of analyzing the chemical composition of the aggregate and admixture for concrete is shown in Table 2, which is only one embodiment, it does not specifically limit the composition of the chemical phase.

In addition, the present invention is characterized in that the strength reduction is prevented by using a high concentration of emulsion emulsifier, that is, a polymer resin emulsifier, in order to prevent a decrease in strength due to many fine particles contained in the unclassified bottom ash. The emulsifier can be used by mixing in water at 1 to 30% by weight relative to the weight of water, preferably adding the polymer resin emulsifier to water at 1 to 30% by weight relative to the weight of water to prepare mixed water, and then mixing the mixed water. It can be mixed with cement.

In addition, the cement of the present invention may be included in 15 to 35% by weight based on the unit weight of 1m ³ of the concrete mixture, wherein the cement is water in the mixed water in which the polymer resin emulsifier is added in 1 ~ 30% by weight relative to the water weight / The mixing ratio of cement may be wet mixed at 40 to 60% by weight.

In particular, the mixing ratio of water / cement is preferably 40 to 60% by weight in terms of strength of concrete. When the mixing ratio of water / cement is less than 40% by weight, a slurry in which building materials are well mixed due to insufficient water content There is a problem in that it is difficult to prepare the composition in the form, whereas if it exceeds 60% by weight it is preferable to mix within the above range because the content of water is too high to cause a problem of low strength of concrete.

In addition, in the case of the concrete composition according to the present invention, at least one of metakaolin, silica fume or calcium carbonate can be used by replacing 1 to 30% by weight with respect to the weight of cement so as to reduce the amount of cement and maintain high strength concrete. have.

In an embodiment of the present invention, when metacarolin was added by substituting up to 30% by weight relative to the weight of cement, it was found that the strength was continuously increased depending on the amount of the metakaolin.

Therefore, it was found that when the admixture such as metakaolin, silica fume and calcium carbonate was added in an amount of 1 to 30% by weight based on the weight of cement, the strength of concrete could be further improved. Furthermore, in the present invention, there is a feature of using a polymer resin emulsifier in order to overcome the problem that the strength of the concrete may be lowered due to the use of unclassified bottom ash, the polymer resin emulsifier that can be used in the present invention is a polyacrylic emulsifier, One or more selected from the group consisting of ethylene butadiene latex emulsifier and vinyl acetate-based emulsifier may be used, and the selected polymer resin emulsifier may be previously added to water to dissolve and then wet kneaded with the concrete mixture to be cured together during cement curing.

In addition, the polymer resin emulsifier may be used containing a solid content of 40% by weight or more relative to the total weight of the emulsifier, and when using the polyacrylic emulsifier is added to the water reducing agent 0.1 ~ 1% by weight compared to the mixed water to have a high viscosity When using the styrene-butadiene-based emulsifier, it is possible to add a retardant 0.1 to 1% by weight relative to the mixed water, which may show a very fast bonding strength by adding the emulsifier and may delay the curing too fast. Can be.

Furthermore, the present invention can provide a method for producing a concrete composition having excellent strength by using the bottom ash containing waste and fine powder as a main aggregate. Preferably, the method for preparing the concrete composition includes a unit weight of 1 m ³ of the concrete mixture. 65 to 85 wt% of the unclassified bottom ash and 15 to 35 wt% of the cement may be mixed with water to which the polymer resin emulsifier is added and then cured.

In the above method, the polymer resin emulsifier may be added in an amount of 1 to 30 wt% based on the weight of water, and the polymer resin emulsifier may be selected from the group consisting of a polyacrylic emulsifier, a styrene butadiene latex emulsifier, and a vinyl acetate emulsifier.

Therefore, the concrete composition using the bottom ash provided by the present invention as a main aggregate and its manufacturing method has the advantage of producing a large amount of concrete using the bottom ash discarded as waste as a building material, replacing the depleted natural aggregate There is also an advantage that can be, in terms of strength and durability has the effect of having a strength or durability of almost the same or more than concrete using natural aggregate.

In addition, since the bottom ash is light in weight per unit volume, it can be utilized as various construction resources such as road pavement, bio block, and concrete flooring of a building.

Furthermore, the unclassified bottom ash according to the present invention can also be utilized in the production of concrete for the ventral pavement, the bottom ash of the main aggregate 5mm sifting the bottom ash of 5mm or more can be used in the production of base concrete, 5mm or less It can be used in the manufacture of surface concrete, to produce a multi-layer concrete pavement, or block concrete.

In addition, the concrete can be prepared by adding a color pigment for concrete in an amount of 2 to 7% by weight based on the unit weight of 1m ³ for the improved packaging material compared to the conventional packaging material.

Hereinafter, the present invention will be described in detail with reference to embodiments and drawings. However, these examples are intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

< Example  1>

Bottom ash  Aggregate As main aggregate  Preparation of one concrete composition

<1-1> Characterization of materials for concrete manufacture

The present inventors collected the bottom ash as it is from the company manager of Samcheonpo Thermal Power Plant before manufacturing the high-strength concrete using the bottom ash as a main aggregate, and measured the physical properties to the results Table 1 It is described in. In addition, the chemical composition of the bottom ash was measured using XRF, and the results are shown in Table 2 below. In addition, the analysis was also analyzed for not only bottom ash but also Portland cement, fly ash, stone aggregate, metakaolin, silica fume and activated kaolin, which are components used for concrete production.

Physical Properties Analysis of Aggregate and Admixture for Concrete Ingredients Specific gravity (g / cm ³ ) Absorption rate (%) Powder level (cm ² / g) Compressive Strength (Kgf / cm ² ) 3 days 7 days 28 days Portland cement 3.15 - 3,450 210  262 348 Bottom ash 2.03 8.12 - - - - Fly ash 2.65 - 4,830 - - - Seoksan aggregate 2.57 1.43 - - - - Metakaolin 2.83 - 5,580 - - - Silica fume 2.16 - 200,000 - - -

 Analysis of Chemical Composition of Concrete Aggregates and Admixtures (wt%) Ingredients SiO ₂ Al ₂ O ₃ Fe ₂ O ₃  CaO   MgO K ₂ O SO ₃ Ig.loss Portland cement 20.70 4.49 2.90 64.33 3.76 0.86 - - Bottom ash 52.20 28.90 9.77 4.83 0.30 1.38 3.60 34.50 Fly ash 57.47 24.16 7.58 4.32 1.21 1.21 3.16 - Seoksan aggregate 55.90 17.31 8.72 6.80 4.83 5.01 - 3.30 Activated kaolin 32.26 16.57 4.11 0.63 5.47 - 0.53 -

Furthermore, the present inventors measured the particle size distribution to confirm that the bottom ash can be used as the main aggregate of concrete production, and the results are shown in FIG. 1.

As a result of analysis, the bottom ash was composed of more than 80% of SiO ₂ and Al ₂ O ₃ , and CaO and Fe ₂ O ₃ were included. In addition, as a result of measuring the particle size distribution of the bottom ash, when compared with the upper and lower particle size distribution of natural sand for general concrete, in particular, it is difficult to use in general concrete because there are too many fine particles of 1mm or less than general natural sand (sand). Could see that it is necessary.

According to the results of chemical analysis, concrete materials including bottom ash do not contain harmful components in concrete. In particular, bottom ash showed very similar chemical results to fly ash. This is because it is mainly composed of the chemical composition of Al ₂ O ₃ and SiO ₂ like fly ash together with the unburnt coal powder containing 12 to 18% by weight of the bottom ash.

As a result of comprehensive analysis of these results, the present inventors confirmed that there is no great difficulty in using bottom ash as a construction material.

<1-2> classification Bottom ash  Used concrete manufacturing

As shown in Table 3 below, a general cement concrete (remicon) specimen having a compressive strength of 240 Kgf / cm 2 was prepared to investigate whether the bottom ash can actually replace natural aggregates (crushed stone and sand). At this time, general portland cement was used as the hydraulic main binder, cement was used for expressing the strength of the hardener, and one general portland cement having a density of 3.15 (kg / m ³ ) was used. The water / cement ratio (W / C) was slump It was added as shown in Table 3 to be 40 to 60% by weight based on 12cm. As the admixture, a papermaking sludge composed of metakaolin and calcium carbonate was used as the pozzolanic material, and naphthalene-based high-performance water reducing agent was used to secure the fluidity of the bottom ash concrete slurry. In the preparation of concrete, each component described in Table 3 below was measured for each blending ratio, and then mixed in a dry manner. Then, water was added according to a water / cement ratio of 12 cm of slump, followed by wet kneading to prepare a specimen. Curing was carried out in air for 24 hours, and after demolding, soaking in a temperature-controlled reservoir to measure the compressive strength after 28 days.

Classification of bottom ash concrete specimens Manufacturing example Crushed aggregate (kg) Fine aggregate
(kg) cement
(kg) Admixture
(kg) water
(kg) Compressive strength
7 days (kg / ㎠) Compressive strength
28 days (kg / ㎠) Remarks One 1019 811 312 0 186 177.5 262.4 Use of steel sand as fine aggregate 2 1019 811 312 0 186 120.0 173.5 Replace all the steel sand content (weight) of Preparation Example 1 with bottom ash. 3 1002 798 328 0 196 110.5 165.2 Increasing the amount of cement in Preparation Example 2 4 986 785 343 0 206 101.0 154 Increasing the amount of cement in Preparation Example 2 5 1019 772 312 0 186 141.9 206 Bottom ash replaces the volume occupied by steel sand in Preparation Example 1
(50% volume substitution) 6 1019 648 312 0 186 156.2 232.1 Bottom ash replaces the volume occupied by steel sand in Preparation Example 1
(100% volume substitution) 7 1019 811 304 7.8 186 119.5 179.9 FLY 2.5% substitution 8 1019 811 298 15.6 186 119.5 191.5 FLY 5.0% substitution 9 1019 811 298 23.4 186 130.0 188 FLY 7.5% substitution 10 1019 811 281 31.2 186 120.1 182.4 FLY 10% substitution 11 1019 811 304 7.8 186 144.3 175.9 M.K 2.5% substitution 12 1019 811 298 15.6 186 119.0 184.2 M.K 5.0% substitution 13 1019 811 281 31.2 186 137.5 211.3 M.K 10% substitution 14 1019 811 265 46.8 186 136.8 210 M.K 20% substitution 15 1019 811 250 62.4 186 137.4 212.3 M.K 30% substitution

As a result of compressive strength analysis for each concrete manufactured with the composition and content as shown in Table 3 above, the test specimen which replaced all the steel sand using the bottom ash classified as less than 5 mm as a fine aggregate, leaving the crushed stone aggregate as the crude aggregate as the weight percent. (Preparation Example 2), but in this case, the strength was significantly reduced to about 65% compared to the specimen using the general steel sand (Preparation Example 1), which is because the bottom ash contains a lot of fine powder, the cement bond is not sufficient However, simply increasing the amount of cement used decreased the strength as in Production Examples 3 and 4. This is because the density of the bottom ash is low, i.e., the weight is low, so that when the same weight is added compared to the sand, the volume of the bottom ash increases, which makes it difficult to compact.

In addition, in the case of light weight bottom ash, it can be seen that volume ratio substitution is more suitable than weight substitution, and in terms of weight, it is found that the addition of about 2/3 is most suitable as the blending amount. In addition, the increase in the amount of addition of the cement was lowered in strength, and as an additional admixture, fly ash (FLY) showed the highest strength at 5% by weight of cement and 30% by weight of metakaolin (M.K).

In addition, a light weight was produced to reduce the amount of bottom ash added to the bulk in the concrete (Manufacturing Examples 5 and 6), in this case, the strength increases significantly as the amount of bottom ash added, but only the apparent density In the case of Preparation Example 6 in which the bottom ash addition amount was further reduced to 2/3 or less in consideration of the packing density compared to Preparation Example 5, it was found that the strength was greatly improved. That is, in order to improve the strength of the bottom ash concrete that contains a lot of fine powder, it was found that the physical properties of the fine aggregate bottom ash can be improved by reducing the compounding amount of the bottom ash in accordance with the volume ratio of the natural fine aggregate, and the volume ratio is the fine aggregate in the concrete. The volume occupied by (grain aggregate) is adjusted in consideration of the tap density.

In addition, the strength of concrete was analyzed by adding fly ash and metakaolin, which are frequently used in ready-mixed concrete, in order to offset the decrease in strength of concrete by adding admixtures. Although the strength-improving effect did not occur significantly. On the other hand, in case of metakaolin, the increase was continued until 30% was added, and it was confirmed that the metakaolin admixture had some effect in the case of the fine powder aggregate. However, when the volume was not mixed, even when metakaolin was added as an admixture, only 80% of the strength of the standard (normal) concrete could be expressed.

<1-3> No classification Bottom ash  Used concrete manufacturing

In the case of the previously manufactured concrete, the classification bottom ash was used. In the case of the classification bottom ash, there is a problem in that the economic cost is increased. Thus, as shown in Table 4, an unclassified bottom ash concrete specimen is manufactured to control the ratio of water and cement and admixture. The strengths due to the incorporation of metakaolin and calcium carbonate were compared.

Comparison of strength of unclassified bottom ash concrete specimen Manufacturing example bottom
Ash (kg) cement
(kg) Admixture
(kg) water
(kg) Cement / Aggregate Ratio C / (S + a) W / C
(weight%) Compressive strength
28 days
(kg / ㎠) Remarks
(Jungnang%) 16 1246 350 0 246 0.281 70% 100.9 17 1235 350 0 210 0.283 60% 110.5 18 1247 350 0 176 0.281 50% 119.8 19 1245 350 0 140 0.281 40% 112.7 20 1212 333 17 176 0.275 53% 123.1 M.K 5% 21 1246 314 36 176 0.252 56% 125.7 M.K 10% 22 1233 297 53 176 0.241 59% 147.8 M.K 15% 23 1285 278 72 176 0.216 63% 150 M.K 20% 24 1246 261 89 176 0.209 67% 148 M.K 25% 25 1255 333 17 176 0.265 53% 107.2 CaCo 5% 26 1234 314 36 176 0.254 56% 113.5 CaCo 10% 27 1222 297 53 176 0.243 59% 116.4 CaCo 15% 28 1271 278 72 176 0.219 63% 110.8 CaCo 20% 29 1265 261 89 176 0.206 67% 98.6 CaCo 25%

In Table 4, the% of M.K represents weight percent based on the weight of cement, and CaCo also represents weight percent based on the weight of cement.

As a result of the production, the bottom ash was not classified as a mixture of coarse aggregate and fine aggregate (residual aggregate), and the concrete was mixed with the main aggregate as it was. In addition, when the metakaolin and paper sludge was added as a admixture, when the 10% of the paper sludge was added, the strength was shown to be maximum, but the strength enhancing effect did not occur significantly. On the other hand, the metakaolin admixture continued to increase even in the case of 20% addition, and it was confirmed that the metakaolin admixture had a certain effect in the case of many fine aggregates. However, since only 60% of the general concrete is developed, it can be seen that a new coupling method is required to utilize the road paving concrete. In addition, the mixing ratio of water and cement was found to have the highest strength in the case of 50% by weight, but 60% was the most suitable for the workability. In the unclassified bottom ash specimen, metakaolin showed the highest strength when 15% by weight of cement was used, and calcium carbonate showed the highest strength when 10% by weight of cement was used. When added in excess of 10% by weight relative to the weight of cement, the strength was found to decrease.

<1-4> according to the addition amount for each resin Bottom ash  Used concrete manufacturing

As described in Example <1-3> in order to further improve the compressive strength of the concrete prepared using a classless bottom ash, concrete was prepared by adding a polymer latex resin bond to the cement bond, in the present invention (Note Styrene Butadiene Latex Resin (SBR Resin III), Polyacryl Resin (MMA Resins I, II, IV) and Vinyl Acetate Resin (EVA Resin V) Was used, and its properties are shown in Table 5 below. In addition, in order to find out whether the resin bond can improve the affinity with the bottom ash aggregate, that is, the bond strength, each resin may be 5 to 30 with respect to the cement content when manufacturing the bottom ash mortar using the bottom ash. After mixing the mixed water added in the% was prepared a specimen to measure the strength of 28 days, the results are shown in Table 6.

General Properties of Used Polymer Latex Resins Suzy Main monomer stabilizator Solid content
content(%) pH Brookfield
Viscosity (cps) Specific gravity (g / cm ³ ) Emulsifier
Characteristic Film formation
Temperature (℃) I MMA I BA 44.8 9.2 171 1.02 Responsive
Emulsifier 10 II MMA II BA, 2EHA 44.8 8.8 28 1.05 Non-ion 0 IV MMA IV 2EHA 47.3 9.0 100 1.01 Negative ion -18 III SBR III SM, 2EHA 44.8 9.2 171 1.02 Negative ion -13 V EVA V 44.9 5.0 1200 1.06 Negative ion 0

Strength comparison analysis of concrete manufactured using bottom ash according to the amount of each resin added Manufacturing example bottom
Ash (kg) cement
(kg) Admixture
(kg) Mixed water
(kg) C / (S + a) w / c
(weight%) Compressive strength
28 days (kg / ㎠) Remarks
(Jungnang%) 30 1245 350 0 200 0.281 57% 104 Resin I5% 31 1243 350 0 200 0.282 57% 111.4 Resin I10% 32 1213 350 0 200 0.289 57% 107.7 Resin I20% 33 1243 350 0 200 0.282 57% 123.7 Resin I30% 34 1285 350 0 210 0.272 60% 105.4 Resin II5% 35 1262 350 0 210 0.277 60% 109.1 Resin II 10% 36 1264 350 0 210 0.277 60% 104.2 Resin II 20% 37 1248 350 0 210 0.280 60% 122.9 Resin II 30% 38 1246 350 0 205 0.281 59% 99.5 Resin III5% 39 1245 350 0 205 0.281 59% 90.1 Resin III10% 40 1245 350 0 205 0.281 59% 60.8 Resin III20% 41 1250 350 0 205 0.280 59% 52.2 Resin III30% 42 1246 350 0 190 0.281 54% 145.5 Resin IV5% 43 1198 350 0 190 0.292 54% 177.8 Resin IV10% 44 1246 350 0 190 0.281 54% 181.3 Resin IV20% 45 1245 350 0 190 0.281 54% 184.5 Resin IV 30% 46 1265 350 0 205 0.277 59% 126.8 Resin V5% 47 1244 350 0 205 0.281 59% 135.1 Resin V10% 48 1222 350 0 205 0.286 59% 157.8 Resin V20% 49 1255 350 0 205 0.279 59% 146.8 Resin V30%

As shown in Table 6, as a result of measuring the compressive strength according to the mixing amount of each resin in the unclassified bottom ash concrete based on the workability, when the acrylic resin IV is added at 30% by weight relative to the water weight, other resins It was found that the compressive strength was remarkably superior to that used. On the other hand, the strength of the rubber-based resin III (SBR system) used for general purposes was rather reduced.

<1-5> Metakaolin  Resin Bond According to Substitution Rate Bottom ash  Manufacture of concrete

Through the fact that the acrylic resin IV has a higher extrusion strength than the other types of resins according to the embodiment <1-4>, in this experiment, a mixed water and a admixture containing 10% by weight of the acrylic resin IV are used. Recycled aggregates or crushed aggregates) were prepared by varying the substitution rate of the aggregate, and the optimum amount of compound that can obtain the required value of 21MPa or more or 24MPa or more through the strength analysis of the prepared concrete, and the results are shown in Table 7 and Table 8 is shown.

Analysis of Resin Bonded Bottom Ash Concrete Strength According to Metakaolin Substitution Rate Manufacturing example bottom
ash
(kg) cement
(kg) MK
Substitution rate
(%) Resin IV10%
Mixed water (kg) C / (S + a) w / c
(weight%) Compressive strength
28 days (kg / ㎠) Remarks 50 1198 350 0% 190 0.292 54% 177.8 standard 51 1250 332.5 5% 190 0.266 57% 198.8 52 1245 315 10% 190 0.253 60% 218.1 53 1246 297.5 15% 190 0.239 64% 217.8 54 1245 280 20% 190 0.225 68% 220 55 1241 262.5 25% 190 0.212 72% 223 56 1262 245 30% 190 0.194 78% 222.8

Strength Analysis of Resin Bonded Bottom Ash Concrete with Different Aggregate Substitution Rates Manufacturing example Bottom ash
(kg) cement
(kg) aggregate
% Substitution Resin IV10%
Mixed water (kg) w / c
(weight%) Compressive strength
28 days (kg / ㎠) Substituted aggregate
Kinds 57 1161 350 0% 190 54% 177.8 standard 58 1231 350 10% 185 53% 199 Recycled Aggregate 59 960 350 25% 177 51% 201 Recycled Aggregate 60 652 350 50% 164 47% 230 Recycled Aggregate 61 372 350 75% 151 43% 235.4 Recycled Aggregate 62 1135 350 10% 184 53% 205.7 Crushed aggregate 63 956 350 25% 177 51% 262 Crushed aggregate 64 668 350 50% 164 47% 283.1 Crushed aggregate 65 374 350 75% 150 43% 308 Crushed aggregate

As a result of the analysis, when metacarolin was substituted, as shown in Table 7, when the metakaolin was added at least 10% by weight, the compressive strength of 21 MPa or more was found, and as shown in Table 8, the crushed aggregate was 25% When applied at the above volume ratio substitution ratio, it was found to exhibit a compressive strength of 24 MPa or more.

So far I looked at the center of the preferred embodiment for the present invention. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

Claims (8)

^On the basis of a unit weight of 1 m ³ of concrete mixture,
65 to 85 weight percent of unclassified bottom ash and 15 to 35 weight percent of a mixture of at least one of metakaolin, silica fume or calcium carbonate mixed with cement in a weight ratio of 1:99 to 25:75,
The cement is a concrete composition using a bottom ash, characterized in that the polymer resin emulsifier is wet-mixed with a water / cement mixing ratio of 40 to 60% by weight in the mixed water is added to 1 to 30% by weight relative to the water weight. The method of claim 1,
The concrete composition using the bottom ash, characterized in that the addition of the non-classified bottom ash substituted by 30 ~ 50% by weight to recycled aggregate or crushed aggregate. delete The method of claim 1,
The polymer resin emulsifier is a polyacrylic emulsifier, a styrene butadiene latex emulsifier and a vinyl acetate-based emulsifier is added to one or more selected in advance and dissolved in water to harden together in cement curing, characterized in that the bottom ash Composition. 5. The method of claim 4,
The polymer resin emulsifier is a concrete composition using a bottom ash, characterized in that containing 40% by weight or more solids relative to the total weight of the emulsifier. Based on a unit weight of 1 m ³ of concrete mixture,
65 to 85% by weight of no-class bottom ash and 15 to 35% by weight of a mixture of at least one of metakaolin, silica fume or calcium carbonate in a weight ratio of 1:99 to 25:75 Method of producing a concrete composition using a bottom ash comprising the step of hardening after mixing. The method according to claim 6,
The polymer resin emulsifier is a method for producing a concrete composition using a bottom ash, characterized in that added to 1 to 30% by weight based on the weight of water. The method according to claim 6,
The polymer resin emulsifier is a polyacrylic emulsifier, a styrene butadiene latex emulsifier and a vinyl acetate-based method of producing a concrete composition using a bottom ash, characterized in that at least one selected from the group consisting of emulsifiers.

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