KR102595960B1 - Composition for manufacturing carbon reduced composites and carbon reduced composites manufactured therefrom - Google Patents

Abstract

The present invention relates to a composition for producing a reduced carbon composite and a reduced carbon composite manufactured therefrom. One aspect of the present invention includes a binder comprising fly ash and blast furnace slag fine powder; Alkali containing at least one selected from the group consisting of sodium hydroxide (NaOH), sodium silicate (Na ₂ SiO ₃ ), potassium carbonate (K ₂ CO ₃ ), calcium hydroxide (Ca(OH) ₂ ), and potassium hydroxide (KOH) activator; A setting retardant containing zinc silicofluoride; Shrinkage reducing agents containing alkylene glycol; Chemical admixtures containing water reducing agents; fine aggregate; It provides a composition for producing a carbon reduction composite comprising; and mixing water.

Description

Composition for producing a carbon reduction composite and a carbon reduction composite manufactured therefrom {COMPOSITION FOR MANUFACTURING CARBON REDUCED COMPOSITES AND CARBON REDUCED COMPOSITES MANUFACTURED THEREFROM}

The present invention relates to a composition for producing a carbon reduction composite and a carbon reduction composite manufactured therefrom.

Currently, globalization is intensifying around the world, with accelerated technological development, expansion of economic scale, and establishment of a global cooperation system to prevent global warming. In the construction field, demands for globalization, increased green construction, and technological innovation are also emerging. In addition, the development of high-performance, high-tech construction material technology is necessary to increase consumer demand for high-performance construction materials considering energy saving, economic efficiency, and safety and to enter the high-tech construction material market.

Carbon reduction composite technology is one of the cutting-edge technologies that will replace cement and concrete in the future, and is a technology that requires active development.

According to some research results, it has been confirmed that approximately 10% of the total CO ₂ emissions in Korea are generated from the concrete industry, and most CO ₂ is known to be generated during cement manufacturing. In addition, it is known that approximately 800 kg to 1000 kg of CO ₂ is generated when manufacturing 1 ton of cement, so research is being actively conducted on materials and methods to replace cement when manufacturing concrete to reduce CO ₂ emissions.

In this regard, research is being conducted to increase strength by mixing fly ash or blast furnace slag fine powder as an alternative to cement and using alkaline activators. However, there are many restrictions on the use of alkaline activators, and the commercialization and practical use of the technology has not yet been achieved. There is a mechanism that has not yet been confirmed. For example, as the amount of liquid alkali activator was increased to secure the required strength, the initial fluidity was quickly lost and rapid hardening occurred, and the use of fine powder of blast furnace slag caused shrinkage and whitening of the surface after hardening. There are problems that arise.

Therefore, a method to solve the above problems is needed in technology to replace cement.

The above-mentioned background technology is possessed or acquired by the inventor in the process of deriving the disclosure of the present application, and cannot necessarily be said to be known technology disclosed to the general public before the present application.

The present invention is intended to solve the above-mentioned problems, and the purpose of the present invention is to provide a composition for manufacturing a carbon reduction composite that can secure performance and workability by using only industrial by-products and functional additives without using cement, and carbon using the same. The goal is to provide an abatement complex.

However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

One aspect of the present invention is a binder comprising fly ash and blast furnace slag fine powder; Alkali containing at least one selected from the group consisting of sodium hydroxide (NaOH), sodium silicate (Na ₂ SiO ₃ ), potassium carbonate (K ₂ CO ₃ ), calcium hydroxide (Ca(OH) ₂ ), and potassium hydroxide (KOH) activator; A setting retardant containing zinc silicofluoride; Shrinkage reducing agents containing alkylene glycol; Chemical admixtures containing water reducing agents; fine aggregate; It provides a composition for producing a carbon reduction composite comprising; and mixing water.

According to one embodiment, it may further include a bleaching occurrence inhibitor containing boric acid.

According to one embodiment, the whitening occurrence inhibitor may be included in an amount of 0.1 to 1 part by weight based on 100 parts by weight of solid content of the binder and the alkali activator.

According to one embodiment, the fly ash may be fly ash containing 7% by weight or more of iron oxide (Fe ₂ O ₃ ).

According to one embodiment, the alkylene glycol may include one or more selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, and butylene glycol.

According to one embodiment, the fly ash may be included in 30% to 70% by weight of the binder, and the blast furnace slag fine powder may be included in 70% to 30% by weight of the binder.

According to one embodiment, the solid content of the alkaline activator may be included in 8 to 16 parts by weight based on 100 parts by weight of the binder.

According to one embodiment, the fine aggregate may include steelmaking slag, ferronickel slag, or a mixture thereof.

According to one embodiment, the setting retardant may be included in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of solid content of the binder and the alkali activator.

According to one embodiment, the shrinkage reducing agent may be included in an amount of 5 kg/m ³ to 10 kg/m ³ based on the unit volume of the carbon reduction composite.

According to one embodiment, the mixing water may be included in an amount of 1 to 35 parts by weight based on 100 parts by weight of solid content of the binder and the alkaline activator.

According to one embodiment, the composition for producing a carbon reduction composite may further include coarse aggregate.

Another aspect of the present invention provides a carbon reduction composite manufactured by curing the composition for producing a carbon reduction composite at room temperature or high temperature.

The composition for producing a reduced carbon composite according to the present invention has the effect of producing a reduced carbon composite with secured workability and high strength by using fly ash and slag, which are industrial by-products, without using cement. This has the effect of significantly reducing carbon emissions. In addition, it is effective in controlling rapid hardening, shrinkage, and surface whitening that occur due to the use of industrial by-products and liquid activators.

The carbon reduction composite manufactured using the composition for manufacturing carbon reduction composite according to the present invention can be cast in situ at room temperature, can secure high strength of 40 MPa or more, and can be used to manufacture PC (Precast Concrete) products using steam curing. There is an effect.

Figure 1 is a graph showing the change in strain (μ) over time when producing a reduced carbon composite using the composition for producing a reduced carbon composite of Examples 1 to 5.
Figure 2 is a graph showing penetration resistance values according to elapsed time for Examples 10 to 15.
Figure 3 is a graph showing penetration resistance values according to elapsed time for Example 10, Example 13, Example 16, and Example 17.
Figure 4 is a graph showing the change in strain (μ) over time when manufacturing a composite using the composition for manufacturing a carbon reduction composite of Examples 18 to 23.
Figure 5 is a surface photograph of a carbon reduction composite manufactured using the composition for producing a carbon reduction composite of Examples 24 and 25.

Hereinafter, embodiments will be described in detail with reference to the attached drawings. However, various changes can be made to the embodiments, so the scope of the patent application is not limited or limited by these embodiments. It should be understood that all changes, equivalents, or substitutes for the embodiments are included in the scope of rights.

The terms used in the examples are for descriptive purposes only and should not be construed as limiting. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the embodiments belong. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless explicitly defined in the present application, should not be interpreted in an ideal or excessively formal sense. No.

In addition, when describing with reference to the accompanying drawings, identical components will be assigned the same reference numerals regardless of the reference numerals, and overlapping descriptions thereof will be omitted. In describing the embodiments, if it is determined that detailed descriptions of related known technologies may unnecessarily obscure the gist of the embodiments, the detailed descriptions are omitted.

Additionally, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being "connected," "coupled," or "connected" to another component, that component may be directly connected or connected to that other component, but there is no need for another component between each component. It should be understood that may be “connected,” “combined,” or “connected.”

Components included in one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, the description given in one embodiment may be applied to other embodiments, and detailed description will be omitted to the extent of overlap.

One aspect of the present invention is a binder comprising fly ash and blast furnace slag fine powder; Alkali containing at least one selected from the group consisting of sodium hydroxide (NaOH), sodium silicate (Na ₂ SiO ₃ ), potassium carbonate (K ₂ CO ₃ ), calcium hydroxide (Ca(OH) ₂ ), and potassium hydroxide (KOH) activator; A setting retardant containing zinc silicofluoride; Shrinkage reducing agents containing alkylene glycol; Chemical admixtures containing water reducing agents; fine aggregate; It provides a composition for producing a carbon reduction composite comprising; and mixing water.

The composition for producing a carbon reduction composite according to the present invention has the effect of producing a carbon reduction composite with secured workability and high strength by using fly ash and blast furnace slag fine powder, which are industrial by-products, without using cement. In particular, unlike conventional cement, which replaced only a portion of cement with industrial by-products, it does not contain cement at all, which has the effect of significantly reducing carbon emissions.

In addition, it has the advantage of being able to significantly control the sudden hardening and shrinkage phenomenon that occurred due to the use of conventional industrial by-products and liquid activators.

According to one embodiment, the composition for producing a carbon reduction composite may further include a whitening occurrence inhibitor containing boric acid.

When manufacturing a carbon reduction composite, an alkali activator is added to fly ash and slag. When the alkali activator solution is added, the resulting composite becomes wet and whitening occurs on the surface. In comparison, when boric acid is included as a whitening inhibitor, surface whitening of the carbon reduction composite can be effectively suppressed.

According to one embodiment, the whitening occurrence inhibitor may be included in an amount of 0.1 to 1 part by weight based on 100 parts by weight of solid content of the binder and the alkali activator.

Here, the solid amount of the binder and the alkaline activator means the total of the solid amount of the binder and the solid amount of the alkaline activator.

Preferably, it may be included in an amount of 0.2 to 1 part by weight based on 100 parts by weight of the solid content of the binder and the alkali activator, and more preferably, it may be included in an amount of 0.3 to 1 part by weight. .

If the content of the whitening inhibitor is less than the above range, whitening on the surface of the carbon reduction composite produced may not be sufficiently suppressed, and if the content of the whitening inhibitor is more than the above range, it may not be dissolved in the composition, thereby strengthening the composite. Problems with deterioration may occur.

The composition for producing a carbon reduction composite according to the present invention includes a binder containing fly ash and blast furnace slag fine powder.

Fly ash and blast furnace slag fine powder are industrial by-products that barely emit CO ₂ , and when used, they have the advantage of not only effectively utilizing industrial by-products but also significantly reducing CO ₂ emissions.

According to one embodiment, the fly ash may be fly ash containing 7% by weight or more of iron oxide (Fe ₂ O ₃ ).

In other words, when analyzing the chemical composition through XRF (based on XRF measurement of Bruker's T8 Tiger model at UNIST UCRF), it may be fly ash containing iron oxide (Fe ₂ O ₃ ) of 7% by weight or more.

For example, the weight percent of iron oxide obtained when analyzing the chemical composition of three different types of fly ash through , dual fly ash 1 or fly ash 2 components can be used.

Fly ash containing more than 7% by weight of iron oxide (Fe ₂ O ₃ ) can improve workability when manufacturing a carbon reduction composite. In other words, even in high-strength formulations with a small number of formulations, the property of not rapidly hardening or rubbing well during mixing can be improved.

For example, when using fly ash containing iron oxide (Fe ₂ O ₃ ) in an amount of less than 7% by weight (for example, 5.4% by weight), initial rapid setting occurs when mixing the composition for producing a carbon reduction composite, To solve this problem, when water is added in addition to the mixing water, the strength decreases as the water content increases. In comparison, when fly ash containing more than 7% by weight of iron oxide (Fe ₂ O ₃ ) is used, the fluidity is improved and the viscosity is reduced, preventing initial rapid setting, and reducing the content of the mixing water. It has the effect of securing high strength.

The composition for producing a carbon reduction composite according to the present invention is composed of sodium hydroxide (NaOH), sodium silicate (Na ₂ SiO ₃ ), potassium carbonate (K ₂ CO ₃ ), calcium hydroxide (Ca(OH)₂), and potassium hydroxide (KOH). It includes an alkaline activator containing at least one selected from the group consisting of

According to one embodiment, the alkaline activator may be added in the form of a solution dissolved in water.

The composition for producing a carbon reduction composite according to the present invention includes a shrinkage reducing agent containing alkylene glycol.

Generally, when using blast furnace slag fine powder, an industrial by-product, when manufacturing a carbon reduction composite, the fine blast furnace slag powder causes shrinkage and cracks on the surface. Therefore, this must be complemented effectively.

The shrinkage reducing agent containing the alkylene glycol can effectively reduce the shrinkage of the carbon-reducing composite and suppress surface cracks that may initially occur.

According to one embodiment, the alkylene glycol may include one or more selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, and butylene glycol.

Preferably, the alkylene glycol may be dipropylene glycol, butylene glycol, or a mixture thereof.

According to one embodiment, the fly ash may be included in 30% to 70% by weight of the binder, and the blast furnace slag fine powder may be included in 70% to 30% by weight of the binder.

If the content of the fly ash is less than the above range, the content of the blast furnace slag fine powder increases, which causes a problem in that the workability maintenance time is shortened and condensation is accelerated. On the other hand, if the above range is exceeded, problems may arise such as a decrease in strength development when curing at room temperature and an increase in curing time when curing at high temperature.

If the content of the blast furnace slag fine powder is less than the above range, the fly ash content increases, resulting in a decrease in strength development during room temperature curing, and the curing time increases during steam curing. On the other hand, if the above range is exceeded, problems such as reduced workability maintenance time and accelerated condensation may occur.

According to one embodiment, the solid content of the alkaline activator may be included in 8 to 16 parts by weight based on 100 parts by weight of the binder.

If the solid content of the alkaline activator is less than the above range, there may be a problem of reduced strength due to a lack of sufficient activator. On the other hand, if the above range is exceeded, workability may be reduced due to excessive activator.

The composition for producing the carbon reduction composite includes a chemical admixture containing a water reducing agent. The water reducing agent may include a low viscosity water reducing agent.

The water reducing agent may be any component used in the technical field without limitation, and for example, a naphthalene-based water reducing agent may be used.

According to one embodiment, the composition for producing a carbon reduction composite may further include coarse aggregate.

The coarse aggregate may have a maximum size of 13 mm, 20 mm, 25 mm, or 40 mm.

According to one embodiment, the coarse aggregate may be included in an amount of 500 kg/m ³ to 1500 kg/m ³ with respect to the unit volume of the carbon reduction composite.

According to one embodiment, the fine aggregate may include steelmaking slag, ferronickel slag, or a mixture thereof.

The steelmaking slag is sand with a round particle shape, and as it is generated during the smelting and steelmaking process, it has a hard surface and a low water absorption rate. Ferronickel slag sand also contains many round particles and has a low water absorption rate.

Therefore, when steelmaking slag or ferronickel slag is used as a fine aggregate, workability can be improved by improving fluidity due to the round particle shape and low water absorption rate, and strength can be improved by reducing the amount of mixing water. In addition, it has the advantage of improved fluidity, allowing on-site casting at room temperature.

According to one embodiment, the fine aggregate may be included in an amount of 700 kg/m ³ to 1800 kg/m ³ with respect to the unit volume of the carbon reduction composite.

The composition for producing a carbon reduction composite according to the present invention includes a setting retardant containing zinc silicofluoride (ZnSiF ₆ ).

The setting retardant containing zinc silicofluoride functions to secure setting time when mixing components of the composition for producing the carbon reduction composite.

When the zinc silicofluoride is used as a setting retardant, a setting delay time of up to about 1 hour can be secured, and through this, work time can be secured and workability can be improved.

Considering that a setting delay time of about 30 minutes is generally secured when a setting retardant is not used, the composition for manufacturing a carbon reduction composite according to the present invention reduces the setting delay time by using zinc silicofluoride as a setting retardant. It has a significantly improved effect.

In particular, among the silicofluoride-based materials, magnesium silicate fluoride rapidly sets, so zinc silicofluoride can be used selectively.

According to one embodiment, the setting retardant may be included in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of solid content of the binder and the alkali activator.

Here, the solid amount of the binder and the alkaline activator means the total of the solid amount of the binder and the solid amount of the alkaline activator.

Preferably, it may be included in an amount of 0.3 parts by weight to 3 parts by weight based on 100 parts by weight of solid content of the binder and the alkaline activator.

When the content of the setting retardant is less than the above range, the setting delay time may be reduced.

According to one embodiment, the shrinkage reducing agent may be included in an amount of 5 kg/m ³ to 10 kg/m ³ based on the unit volume of the carbon reduction composite.

Preferably, with respect to the unit volume of the carbon reduction composite, it may be included in the range of 6 kg/m ³ to 9 kg/m ³ , and more preferably, it may be included in the range of 6 kg/m ³ to 8 kg/m ³ It may be.

If the content of the shrinkage reducing agent is less than the above range, the shrinkage reduction effect of the carbon-reduced composite may not appear, and if it exceeds the above range, the problem of lowering the compressive strength may occur.

According to one embodiment, the mixing water may be included in an amount of 1 to 35 parts by weight based on 100 parts by weight of solid content of the binder and the alkaline activator.

Here, the solid content of the binder and the alkaline activator means the total of the solid content of the binder and the solid content of the alkaline activator.

That is, it may be included in an amount of 35 parts by weight or less based on 100 parts by weight of solid content of the binder and the alkaline activator.

The composition for producing a carbon reduction composite according to the present invention has the effect of significantly improving the strength of the carbon reduction composite by reducing the amount of mixing water.

If the content of the mixing water exceeds the above range, the strength of the carbon reduction composite produced may be lowered.

The carbon reduction composite manufactured according to the present invention has the effect of ensuring high strength by using a binder with improved fluidity and an alkali activator, with a low relative content of the added mixing water.

According to one embodiment, the composition for producing a carbon reduction composite may be cement-free.

Another aspect of the present invention provides a carbon reduction composite manufactured by curing the composition for producing a carbon reduction composite at room temperature or high temperature.

The carbon reduction composite according to the present invention can be cast in situ at room temperature, can secure a high strength of more than 40 MPa without using cement, and can be used to manufacture PC (Precast Concrete) products using steam curing.

Hereinafter, the present invention will be described in more detail through examples and comparative examples.

However, the following examples are only for illustrating the present invention, and the content of the present invention is not limited to the following examples.

<Experimental Example 1> Effect of shrinkage reducing agent content

1) Experimental method

Reduced carbon composites were manufactured using compositions for manufacturing reduced carbon composites prepared by varying the amount of shrinkage reducing agent used, and workability, degree of shrinkage, and compressive strength were measured for each example.

The composition for producing a carbon reduction composite is fly ash (specific gravity 2.25), blast furnace slag fine powder (specific gravity 2.9), ferronickel slag fine aggregate (specific gravity 3.0, water absorption 0.6%), 20 mm coarse aggregate (specific gravity 2.7, water absorption 0.5%), NaOH solution (solid content 50% + water 50%), Na ₂ SiO ₃ solution (solid content 44% + water 56%), boric acid (99.5%, powder), PNS (naphthalene base water reducing agent, solid content 40%), shrinkage reducing agent (diplo) Philene glycol and butylene glycol) and low-viscosity water reducing agent (solids 30%) were mixed with mixing water. Using this, a carbon reduction composite was manufactured by curing at room temperature and 60°C.

To evaluate workability, slump flow was measured according to KS F 2594.

The shrinkage experiment was conducted by installing a Vibrating Wire Gauge in the center of the 40x40x400mm beam mold and automatically measuring the amount of shrinkage once a minute using a dedicated data logger. After pouring, the seal was cured for 24 hours to prevent moisture loss, and after 24 hours, the seal was removed, demolded, and drying shrinkage was measured. A series of operations from pouring to shrinkage measurement were carried out inside a large constant temperature and humidity room, and the conditions were a temperature of 23°C and a humidity of 60%.

To measure compressive strength, a compressive strength test according to KS F 2405 was conducted. The composite was poured into a cylindrical mold with a diameter of 100 mm and a height of 200 mm, and after pouring, it was sealed with a zipper bag and cured at room temperature or at high temperature. In particular, in the case of high temperature curing, considering the working hours of the PC factory, the initial rise time from 20 ℃ to 60 ℃ after transposition was about 2 hours, curing was maintained at 60 ℃ for 6 hours, and then the temperature increased to 20 ℃ for 4 hours. The temperature was lowered. 24 hours after production, it was demolded, sealed in a zipper bag, and stored in a constant temperature and humidity room. After manufacturing, the compressive strength was measured using a compressive strength meter according to the age.

The specific composition of each example is shown in Table 1.

* W = mixing water = 1 m ³ Total amount of water used in mixing = water + water in Na ₂ SiO ₃ solution + water in NaOH solution + water in PNS + water in low-viscosity water reducing agent = 136.6kg/ ^m3

* G = fly ash + blast furnace slag fine powder + solids contained in Na ₂ SiO ₃ solution + solids contained in NaOH solution = 455.2 kg/m ³

* W/G is the ratio of W and G

2) Evaluation of shrinkage pattern and workability

The results of the experiment (one mixing volume = 40 Liter, Mixing time 2 minutes) of each example are shown in Table 2 and Figure 1.

Figure 1 is a graph showing the change in strain (μ) over time when producing a reduced carbon composite using the composition for producing a reduced carbon composite of Examples 1 to 5.

Referring to Table 1 and Figure 1, it can be seen that shrinkage is reduced as the content of the shrinkage reducing agent increases, and in Examples 4 and 5, the shrinkage reduction effect is significant.

3) Compressive strength evaluation

The compressive strength measurement results of each example are shown in Table 3.

Referring to Table 3, all examples showed high compressive strength results of 40 MPa or more. In particular, in the case of room temperature curing, Example 1 showed the highest compressive strength, and it can be seen that the compressive strength decreases as the amount of shrinkage reducing agent used increases.

In addition, high temperature curing showed a similar trend to room temperature curing.

According to Example 4, when 6 kg/m ³ of shrinkage reducer was added, the 28-day compressive strength was 50.0 MPa, and according to Example 6, even when 6 kg/m ³ of shrinkage reducer was added, if a low-viscosity water reducer was added, compression decreased. The strength increased to 60.1 MPa, showing a tendency to recover the strength of Example 1 without the use of a shrinkage reducing agent.

<Experimental Example 2> Effect of blast furnace slag fine powder content ratio

1) Experimental method

Reduced carbon composites were manufactured using compositions for manufacturing reduced carbon composites prepared by varying the amount of blast furnace slag fine powder used, and workability and compressive strength were measured for each example.

Each experiment was performed using the same method as described in Experimental Example 1.

The specific composition of each example is shown in Table 4.

* W = mixing water = 1 m ³ Total amount of water used in mixing = water + water in Na ₂ SiO ₃ solution + water in NaOH solution + water in PNS + water in low-viscosity water reducing agent = 136.6kg/ ^m3

* G = fly ash + blast furnace slag fine powder + solids contained in Na ₂ SiO ₃ solution + solids contained in NaOH solution = 455.2 kg/m ³

* W/G is the ratio of W and G

2) Workability evaluation

The results of the experiment (one mixing volume = 40 Liter, Mixing time 2 minutes) of each example are shown in Table 5.

Referring to Table 5, it can be seen that workability is secured when manufacturing a composite using the composition for manufacturing a carbon reduction composite according to the present invention.

3) Compressive strength evaluation

The compressive strength measurement results of each example are shown in Table 6.

Referring to Table 6, it can be seen that the compressive strength was significantly reduced in Example 9 in which blast furnace slag fine powder was not used.

<Experimental Example 3> Setting delay effect due to addition of zinc silicofluoride

1) Experiment method

The setting delay effect was evaluated for each example of a carbon-reducing composite manufactured by varying the amount of zinc silicofluoride (Zn ₂ SiF ₆ , hereinafter referred to as ZF). To measure the setting, a carbon-reducing composite mortar was manufactured by excluding the coarse aggregate, and the setting delay effect was evaluated by measuring the setting of the mortar.

In this experimental example, the NaOH solution was 14 M and had a solid content of 26%, and the Na ₂ SiO ₃ solution had a solid content of 44%. A polycarboxylate-based water reducing agent (PCE50, solids 50%) was used. Zinc silicate was used in powder form.

After manufacturing the composite mortar, flow was measured. The frame for measuring flow was 50 mm high, the diameter of the hole above the frame was 70 mm, and the diameter of the hole below the frame was 100 mm, and the flow that flowed and spread on its own was measured. The flow speed was evaluated by measuring the time for the mortar flow to reach a diameter of 200 mm while flowing on its own.

Afterwards, the setting time of the mortar was measured using the KS F 2436 test method for the setting time of concrete using a penetration resistance needle.

The specific composition of each example is shown in Table 7.

* W = Blending water = 1 m ³ Total amount of water used in mixing = Water + water contained in Na ₂ SiO ₃ solution + water contained in NaOH solution + water contained in PCE50 (water reducing agent) = 237.4 kg/m ³

* G = fly ash + blast furnace slag fine powder + solids contained in Na ₂ SiO ₃ solution + solids contained in NaOH solution = 848.0 kg/m ³

* W/G is the ratio of W and G

2) Experiment results

The results of the experiment (mortar volume 2 Liter, mixing time 3 minutes) of each example are shown in Table 8.

Figure 2 is a graph showing penetration resistance values according to elapsed time for Examples 10 to 15.

Referring to Figure 2, it can be seen that the setting delay effect increases as the amount of zinc silicofluoride used increases.

Figure 3 is a graph showing penetration resistance values according to elapsed time for Example 10, Example 13, Example 16, and Example 17.

Referring to Figure 3, it can be seen that the setting delay effect was the highest in Example 16 in which zinc silicofluoride, boric acid, and shrinkage reducing agent were all used.

3) Compressive strength evaluation

The compressive strength measurement results of Examples 10, 13, and 16 are shown in Table 9.

Referring to Table 9, in the case of high temperature curing, when 60°C was maintained for 24 hours, the compressive strength was high at 69.0 MPa to 74.5 MPa. When compared to the compressive strength results in Table 3 where the high temperature curing time at 60°C was 6 hours, the compressive strength increased as the high temperature curing time was extended to 24 hours.

In addition, when curing at room temperature, strength development was delayed due to the addition of zinc silicofluoride as in Example 13, and strength development was significantly delayed due to the addition of a shrinkage reducer as in Example 16, but during high temperature curing, zinc silicofluoride was added. , it was found that there was no decrease in strength due to the addition of shrinkage reducing agent.

<Experimental Example 4> Effect of adding zinc silicofluoride and shrinkage reducing agent

1) Experimental method

After adding zinc silicofluoride, which has a setting-retarding effect, to the composition for producing a reduced-carbon composite, the reduced-carbon composite was prepared by varying the amount of shrinkage reducing agent used, and the workability, degree of shrinkage, and compressive strength were measured for each example.

The composition for producing a carbon reduction composite is fly ash (specific gravity 2.25), blast furnace slag fine powder (specific gravity 2.9), Na ₂ SiO ₃ solution (solid content 44%), NaOH solution (solid content 26%), and ferronickel slag fine aggregate (specific gravity 3.0, water absorption rate 0.6). %), 13 mm coarse aggregate (specific gravity 0.7, water absorption 0.5%), PCE50 (polycarboxylate base water reducing agent, solid content 50%), zinc silicofluoride (Zn ₂ SiF ₆ , expressed as ZF), shrinkage reducing agent (diplo) It was manufactured by mixing pylene glycol and butylene glycol) and boric acid (99.5%, powder). Using this, a carbon reduction composite was manufactured by curing at room temperature and high temperature (60°C).

Workability was adjusted through visual evaluation to a level where viscosity was low and slump flow type workability was observed.

The shrinkage experiment was conducted by installing a Vibrating Wire Gauge in the center of the 40x40x400mm beam mold and automatically measuring the amount of shrinkage once a minute using a dedicated data logger. After pouring, the seal was cured for 24 hours to prevent moisture loss, and after 24 hours, the seal was removed, demolded, and drying shrinkage was measured. A series of operations from pouring to shrinkage measurement were carried out inside a large constant temperature and humidity room, and the conditions were a temperature of 23°C and a humidity of 60%.

To measure compressive strength, a compressive strength test according to KS F 2405 was conducted. The composite was poured into a cylindrical mold, and after pouring, everything was sealed with a zipper bag and cured at room temperature or at high temperature. In particular, in the case of high temperature curing, considering the working hours of the PC factory, the initial rise time from 20 ℃ to 60 ℃ after transposition was about 2 hours, curing was maintained at 60 ℃ for 6 hours, and then the temperature increased to 20 ℃ for 4 hours. The temperature was lowered. 24 hours after production, it was demolded, sealed in a zipper bag, and stored in a constant temperature and humidity room. After manufacturing, the compressive strength was measured using a compressive strength meter according to the age.

The specific composition of each example is shown in Table 10.

* W = 1 m ³ Total amount of water used in the formulation = water + water in Na ₂ SiO ₃ solution + water in NaOH solution + water in PCE50 = 141 kg/m ³

* G = fly ash + blast furnace slag fine powder + solids contained in Na ₂ SiO ₃ solution + solids contained in NaOH solution = 455 kg/m ³

* W/G is the ratio of W and G

2) Evaluation of shrinkage pattern and workability

The results of the experiment of each example (mixing volume once = 5 Liters, Mixing time 2 minutes) are shown in Table 11 and Figure 4.

Table 11 shows the results of measuring the temperature in an unhardened state after mixing the composite.

Figure 4 is a graph showing the change in strain (μ) over time when manufacturing a composite using the composition for manufacturing a carbon reduction composite of Examples 18 to 23.

Referring to Table 11 and Figure 4, it can be seen that the degree of shrinkage decreases as the content of the shrinkage reducing agent increases even when zinc silicofluoride is added.

3) Compressive strength evaluation

The compressive strength measurement results of each example (high temperature 60°C, 6 hours) are shown in Table 12.

Referring to Table 12, as the amount of shrinkage reducing agent used increased, the compressive strength after 28 days of room temperature curing decreased.

However, when 6 kg of shrinkage reducing agent was added as in Example 20, the result was 39.4 MPa. However, when 3.64 kg of boric acid was added to 6 kg of shrinkage reducing agent as in Example 22, the compressive strength increased to 51.3 MPa, and Example 23 As shown, when 1.2% zinc silicofluoride was added to 6 kg of shrinkage reducing agent, the strength increased to 60.1 MPa, showing a tendency to recover the strength of Example 18.

Even in high-temperature curing, the strength level was low because the high-temperature curing time at 60°C was short at 6 hours, but the compressive strength recovery tendency was the same when boric acid was added and zinc silicofluoride was added. As shown in Table 9, if the high temperature curing time increases, the compressive strength is estimated to increase further.

<Experimental Example 5> Confirmation of the effect of adding boric acid

1) Experimental method

In order to confirm the effect of suppressing the occurrence of surface whitening caused by the addition of boric acid, the surfaces of the mortars prepared in Examples 24 and 25 were observed.

The materials used in this experimental example were fly ash (specific gravity 2.25), blast furnace slag fine powder (specific gravity 2.9), Na ₂ SiO ₃ solution (solid content 44%), NaOH solution (solid content 50%), steel slag fine aggregate (specific gravity 3.76, water absorption rate 0.5%), PNS (naphthalene-based water reducing agent, solid content 40%), and boric acid (99.5%, powder) were mixed with mixing water. It was cured at room temperature.

2) Experiment results

Figure 5 is a surface photograph of a carbon reduction composite manufactured using the composition for producing a carbon reduction composite of Examples 24 and 25.

Referring to Figure 5, it can be seen that the surface whitening phenomenon was suppressed in Example 24 in which boric acid was added.

Although the embodiments have been described with limited drawings as described above, those skilled in the art can apply various technical modifications and variations based on the above. For example, the described techniques are performed in a different order than the described method, and/or components of the described system, structure, device, circuit, etc. are combined or combined in a different form than the described method, or other components are used. Alternatively, appropriate results may be achieved even if substituted or substituted by an equivalent.

Therefore, other implementations, other embodiments, and equivalents of the claims also fall within the scope of the following claims.

Claims (13)

A binder containing fly ash and blast furnace slag fine powder;
Alkali containing at least one selected from the group consisting of sodium hydroxide (NaOH), sodium silicate (Na ₂ SiO ₃ ), potassium carbonate (K ₂ CO ₃ ), calcium hydroxide (Ca(OH) ₂ ), and potassium hydroxide (KOH) activator;
A setting retardant containing zinc silicofluoride;
Shrinkage reducing agents containing alkylene glycol;
Chemical admixtures containing water reducing agents;
fine aggregate;
mixing water; and
A composition for producing a carbon reduction composite comprising a whitening occurrence inhibitor containing boric acid,
The whitening occurrence inhibitor is contained in an amount of 0.1 part by weight to 1 part by weight based on 100 parts by weight of solid content of the binder and the alkali activator,
The solid content of the alkaline activator is 8 to 16 parts by weight based on 100 parts by weight of the binder,
The setting retardant is contained in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of solid content of the binder and the alkali activator,
The shrinkage reducing agent is contained in an amount of 5 kg/m ³ to 10 kg/m ³ based on the unit volume of the carbon reduction composite,
The mixing water is contained in an amount of 1 to 35 parts by weight based on 100 parts by weight of the solid content of the binder and the alkaline activator.
Composition for manufacturing carbon reduction composite.
delete delete According to paragraph 1,
The fly ash is fly ash containing more than 7% by weight of iron oxide (Fe ₂ O ₃ ),
Composition for manufacturing carbon reduction composite.
According to paragraph 1,
The alkylene glycol includes one or more selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, and butylene glycol,
Composition for manufacturing carbon reduction composite.
According to paragraph 1,
The fly ash is included in 30% by weight to 70% by weight of the binder,
The blast furnace slag fine powder is contained in 70% by weight to 30% by weight of the binder,
Composition for manufacturing carbon reduction composite.
delete According to paragraph 1,
The fine aggregate includes steelmaking slag, ferronickel slag, or mixtures thereof,
Composition for manufacturing carbon reduction composite.
delete delete delete According to paragraph 1,
Further comprising coarse aggregate;
Composition for manufacturing carbon reduction composite.
Manufactured by curing the composition for producing a carbon reduction composite of claim 1,
Carbon reduction complex.

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