KR102102864B1 - High- performance environmentally-friendly hardening agent and soil pavement concrete composition including the same - Google Patents

Abstract

The present invention relates to a hardener for soil-pavement concrete comprising natural organic lime, dolomitic limestone and blast-furnace slag cement, and a soil-pavement concrete composition comprising the same. The high-performance eco-friendly hardener according to the present invention includes natural organic lime, dolomitic limestone, ground-granulated blast-furnace slag, and the like, and thus improves the quality of soil-pavement concrete such as enhancing strength and increasing freeze-thaw resistance. The hardener also includes industrial by-products that have been conventionally discarded, and thus solves problems of a domestic landfill cost part, landfill shortage part, environmental pollution part, and construction and civil engineering fields, thereby being eco-friendly and economical.

Description

High performance eco-friendly hardener and soil pavement concrete composition containing the same {HIGH-PERFORMANCE ENVIRONMENTALLY-FRIENDLY HARDENING AGENT AND SOIL PAVEMENT CONCRETE COMPOSITION INCLUDING THE SAME}

The present invention relates to a curing agent included in the concrete composition for soil pavement and a concrete composition for soil pavement comprising the same.

Soil-paved concrete is manufactured using ocher, and is environmentally friendly and reproduces colors in natural ocher color. Unlike ordinary pavement, it has a smooth walking feel and emits far-infrared rays from the ocher, thereby enhancing citizen's health, and it is a loess material. It is known as environmentally friendly pavement concrete that creates an environment and removes toxic substances and odors.

Currently, there is a dry method and a wet method in the domestic pavement concrete pavement method related to landscape packaging, and the dry method is a method of mixing soil and a large amount of cement and hardener and laying it under dry rain to compact it with rollers, etc. Compared with the method, there is no advantage of additional resource consumption due to the use of on-site soil, and it does not require a treatment process at the time of disposal, so it has the advantage of less occurrence of secondary pollution, but has the disadvantage of lowering strength, cracking and durability of freezing and thawing. Therefore, the utilization performance is poor compared to the wet method. In addition, the soil pavement concrete by the wet method is attracting attention as a cause of environmental pollution as a large amount of cement is used and various chemical admixtures are used, and it is necessary to prepare a countermeasure to solve it.

Korean Registered Patent No. 10-1335835 (Registration Date: 2013. 11. 26.) Korean Registered Patent No. 10-1154280 (Registration date: 2012. 06. 01.)

The technical problem to be solved by the present invention is a dry soil pavement material that can maximize eco-friendliness while securing strength, freeze-thaw durability, which is an advantage of wet soil pavement, and an environmental load-reducing curing agent and dry soil pavement concrete containing the same. Is to provide.

In the description of the present invention, when it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the subject matter of the present invention, detailed descriptions thereof will be omitted.

The embodiments according to the concept of the present invention may be modified in various ways and have various forms, and thus, specific embodiments will be illustrated in the drawings and described in detail in the present specification or application. However, this is not intended to limit the embodiment according to the concept of the present invention to a specific disclosure form, and it should be understood to include all modifications, equivalents, or substitutes included in the spirit and scope of the present invention.

The terms used in this specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as “include” or “have” are intended to indicate that a feature, number, step, action, component, part, or combination thereof described is present, and one or more other features or numbers. It should be understood that it does not preclude the presence or addition possibilities of, steps, actions, components, parts or combinations thereof.

In order to achieve the above technical problem, the present invention proposes a hardener for soil-paved concrete containing blast furnace slag cement containing natural organic lime, dolomitic lime and blast furnace slag powder. .

The natural organic lime (natural organic lime) is a highly reactive lime mainly made of CaCO ₃ components prepared by special sorting processing of oyster shells and the like, and is mainly used as an agricultural soil improvement and stabilizer.

The dolomitic lime, also called dolomite lime, is high in MgO content by mixing magnesium carbonate and lime carbonate, and is obtained by heating and grinding a mineral called dolomite.

The natural organic lime and goji lime can be included in the curing agent according to the present invention in an amount of 10 to 20% by weight based on the total weight.

Preferably, the natural organic lime and high-earth lime can be included in the curing agent according to the present invention in a weight ratio of 2: 8 to 8: 2, and more preferably, in a weight ratio of 5: 5.

The blast furnace slag cement may include blast furnace slag powder and fine particle cement having small particles collected in a separator bag filter during a cement grinding process.

In addition, the blast furnace slag cement may be included in the curing agent according to the present invention in an amount of 80 to 90% by weight, wherein the blast furnace slag preferably contains 30 to 50% by weight of blast furnace slag fine powder, more preferably The blast furnace slag may include fine powder and particulate cement in a weight ratio of 3: 7.

As described above, the present invention combines blast furnace slag cement containing blast furnace slag fine powder, which is a recycled resource, with natural organic lime and goji lime, which are eco-friendly materials used for existing agriculture, in hardener, which is a core element technology of soil-paved concrete, and chemicals of each material. Through the auxiliary action, it is possible to achieve stable strength development and environmental load reduction of the hardener, and to provide eco-friendliness and secure performance of natural soil-paved concrete using natural organic lime and high-earth lime.

On the other hand, the curing agent according to the present invention may be added to the soil pavement concrete containing soil, such as masato, ocher, and provided in the dry soil pavement method, and an example of the dry soil pavement method may include (a) packaging Compacting the ground; (b) laying and compacting the soil paved concrete composition of claim 8 on the ground; And (c) curing the laid and compacted soil-paved concrete composition.

The high-performance eco-friendly curing agent according to the present invention includes natural organic lime, high-earth lime, fine blast furnace slag, etc., thereby improving the quality of soil-paved concrete, such as enhancing strength and increasing freeze-thaw resistance, as well as including industrial by-products that were conventionally discarded. Therefore, it is eco-friendly and economical by improving the problems of the landfill cost in Korea, the lack of landfill, environmental pollution, and construction and civil engineering.

1 is a process flow chart showing the process of manufacturing mortar in Example 1 herein.
Figure 2 is a graph showing the flow (flow) according to the mixing ratio of natural organic lime and high-earth lime in Example 1 herein.
Figure 3 is a graph showing the amount of air according to the mixing ratio of natural organic lime and high-earth lime in Example 1 herein.
Figure 4 is a graph showing the compressive strength of the material combination ratio of the curing agent in the mortar of the compounding ratio (C: S) 1: 5 in Example 1 herein.
5 is a graph showing the compressive strength according to the material combination ratio of the curing agent in the mortar having a compounding ratio (C: S) 1: 3 in Example 1 of the present application.
6 is a graph showing the flexural strength according to the material combination ratio of the curing agent in the mortar having a compounding ratio (C: S) 1: 5 in Example 1 of the present application.
7 is a graph showing the flexural strength of the material combination ratio of the curing agent in the mortar having a compounding ratio (C: S) 1: 3 in Example 1 of the present application.
Figure 8 shows an SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 10% by weight, G 0% by weight) of 7 days of age in Example 1 herein.
Figure 9 shows a SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 7.5% by weight, G 2.5% by weight) of 7 days of age in Example 1 herein.
Figure 10 shows an SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 5% by weight, G 5% by weight) of 7 days of age in Example 1 herein.
11 shows an SEM photograph of the curing agent (BS 27 wt%, FC 63 wt%, H 2.5 wt%, G 7.5 wt%) of 7 days of age in Example 1 herein.
12 is a SEM photograph of the curing agent (BS 27 wt%, FC 63 wt%, H 0 wt%, G 10 wt%) of 7 days of age in Example 1 of the present application.
Figure 13 shows a SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 10% by weight, G 0% by weight) of 28 days of age in Example 1 herein.
14 is a SEM photograph of the curing agent (BS 27 wt%, FC 63 wt%, H 7.5 wt%, G 2.5 wt%) of 28 days of age in Example 1 herein.
15 is a SEM photograph of the curing agent (BS 27 wt%, FC 63 wt%, H 5 wt%, G 5 wt%) of 28 days of age in Example 1 herein.
Figure 16 shows a SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 2.5% by weight, G 7.5% by weight) of 28 days of age in Example 1 herein.
Figure 17 shows the SEM photograph of the curing agent (BS 27% by weight, FC 63% by weight, H 0% by weight, G 10% by weight) of 28 days of age in Example 1 herein.
18 is a diagram showing the distribution of pores up to a size of 0.001 to 0.1 μm at 7 days of age according to the combination ratio of the curing agent in the mortar having a compounding ratio (C: S) of 1: 3 in Example 1 of the present application.
19 is a diagram showing the distribution of pores up to a size of 0.001 to 0.1 μm at 28 days of age according to the curing agent combination ratio in the mortar having a compounding ratio (C: S) of 1: 3 in Example 1 of the present application.
20 is a result of XRD analysis according to the mixing ratio of natural organic lime and high-earth lime materials in Example 1 of the present application.
21 is a process flow chart showing a process for producing concrete in Example 2 herein.
22 is a graph showing the compressive strength of concrete according to age according to the curing agent substitution rate change in Example 2.
23 is a graph showing the flexural strength of concrete according to age according to the curing agent substitution rate in Example 2 of the present application.
24 is a graph showing the compressive strength after freezing and thawing of concrete according to the change of the curing agent substitution rate in Example 2 of the present application.

Hereinafter, the present invention will be described in more detail with reference to Examples.

The embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not interpreted to be limited to the embodiments described below. The embodiments of the present specification are provided to more fully describe the present specification to those skilled in the art.

<Example 1> Preparation of blast furnace slag mortar including natural organic lime and high-earth lime, and analysis of characteristics and microstructure of the mortar

Table 1 shows the experimental plans for the engineering characteristics and microstructure of blast furnace slag mortar, which combines natural organic lime and goji lime, and the formulations are shown in Table 2. same. First, the mixing ratio of mortar was 1: 3, 1: 5, and W / C was 70% and 100%. The target flow was 150 ± 25 mm, the target air volume was 4.5 ± 1.5%, and the hardener material was blast furnace slag (BS), natural organic lime (H), high-lime lime (G), and fine particle cement (FC). Blast furnace slag cement (BSC) 90%, BS: FC composition ratio was planned to be 5: 5, 7: 3 2 levels, and the ratio of natural organic lime (H) and goji lime (G) was 10: 0 ~ 0:10. Up to 5 levels, the experiment was planned. As experiments, it was planned to measure flow, air volume in unstiffened mortar, SEM photographing at age 7, 28 days in hardened mortar, porosimeter, compressive strength and flexural strength at XRD, age 7, 28 days.

<Table 1>

<Table 2>

1. Materials used

(1) Cement

As the cement used in this experiment, one type of ordinary Portland cement from A company in Korea was used, and the physical and chemical properties are shown in Table 3.

<Table 3>

(2) Natural organic lime

The organic lime used in this experiment was a domestic D product, and its physical and chemical properties are shown in Table 4.

<Table 4>

(3) Goto lime

For the high-lime lime used in this experiment, domestic D company products were used, and the physical and chemical properties are shown in Table 5.

<Table 5>

(4) Masato

The masato used in this experiment was a domestic D company, and the physical and chemical properties are shown in Table 6.

Table 6.

(5) Particulate cement

As the bonding material used in this experiment, the product of domestic A was used as the fine particle cement, and the physical and chemical properties are shown in Table 7.

<Table 7>

(6) blast furnace slag

As the binder used in this experiment, three types of blast furnace slag fine powder were used in the domestic company A, and the physical and chemical properties are shown in Table 8.

Table 8

2. Experimental method

(1) Mortar mixing

The mortar is mixed according to the procedure shown in FIG. 1 using a mortar mixer. That is, the mixer is divided into two stages of low speed and medium speed according to KS L 5109 using a 7L electric mixer. Experimental materials such as fine aggregate, fine particle cement, natural organic lime, and high-lime lime are put in, and then dry at low speed for 30 seconds. Stop the mixer and leave for 30 seconds. After changing the mixer to 2nd speed, add the metered chemical admixture and water and mix for 30 seconds. The mixer is stopped and the mortar is left for 90 seconds. At this time, all the mortar attached to the side of the container during the first 15 seconds is scraped off in the batch. Mix in second speed for 60 seconds and complete mixing.

(2) Table flow

As a measure of the fluidity of the hardened mortar, the flow measurement uses a tester of KS L 5111 (test flow table) .After wiping the top of the flow plate with a dry cloth, place the mold, fill the mortar with about 25 mm, and then use a compaction rod. After slicing and refilling the mold completely, do the same as the first layer, pick it with a trowel so that the top is horizontal, leave it for about 1 minute, remove the surrounding water and take out the mold vertically. After dropping the test plate of the 12 mm high flow tester 25 times for 15 seconds, immediately measure four diameters of the mortar spread on the flow plate at approximately equal intervals, and use the average diameter as the flow value.

(3) Air volume

The air volume is measured according to the air chamber pressure method of KS F 2421. That is, the sample is placed in two layers in a cylindrical container made of metal with a mechanically polished inner surface, and equally chopped 25 times to match the air pressure in the air chamber to the initial pressure. After that, open the operation valve, hit the side surface with a wooden hammer so that the pressure is evenly spread, and then open the operation valve completely, and after the instructions are stable, read the scale to 1 decimal place and record the value.

(4) Preparation of test specimen

For the production of mortar specimens, 40 × 40 × 160 mm specimens were prepared.

(5) Compressive strength

Compressive strength, as the basic property of mortar, is measured after curing for a certain period of time in accordance with the "Test Method for Compressive Strength of Soil Cement by Specimen Used in KS F 2326 Flexural Strength Test". The compressive strength tester used at this time is measured using a hydraulic 3 GN UTM.

(6) Flexural strength

As a basic property of mortar, a test specimen is manufactured with a size of 40 × 40 × 160 mm according to the “Testing Method for Bending Strength of Soil Cement of KS F 2325”. The flexural strength is the average value of three specimens and ends at one decimal place.

3. Experimental results and analysis

3.1 Uncured mortar properties

Table 9 shows the experimental results of the hardened blast furnace slag mortar according to the substitution rate of the natural organic lime and high-earth lime.

(1) Flow

2 is a graph showing the flow according to the mixing ratio of natural organic lime and goji lime. First, in the case of the mortar mixing ratio 1: 5, the composition ratio of the curing agent BSC (5: 5) was found to decrease the fluidity when the mixing ratio was biased. In addition, in the case of the curing agent composition ratio BSC (7: 3), it was found that the fluidity decreased compared to the curing agent composition ratio BSC (5: 5). This is considered to be an increase in viscosity as the proportion of high-powder fine particle cement (FC) in the curing agent composition ratio increases. In the case of mortar compounding ratio 1: 3, the fluidity tended to decrease as the mixing ratio of natural organic lime and high-lime lime according to the composition ratio of all hardeners was biased to high-earth lime. This increased viscosity of high-lime lime of fine particles. We believe this is due to an increase in liquidity. In addition, in the case of the mortar compounding ratio 1: 7, it was impossible to measure the float at all the composition ratios of the particulate cement and the blast furnace slag.

(2) Air volume

Figure 3 is a graph showing the amount of air according to the mixing ratio of natural organic lime and goji lime. In the case of the mortar compounding ratio 1: 5, the amount of air increased as the mixing ratio of the organic lime increased in the composition ratio of all hardeners. This is because the hexagonal particle shape of the organic lime does not fill the tissue in the mortar tightly, resulting in trapped air. It is judged as an increase in air volume. In the case of the mortar mixing ratio of 1: 3, the air volume was satisfied at all the composition ratios, and the air volume decreased as the mixing ratio of high-lime lime increased. This also applies to the mortar mixing ratio of 1: 5, and it is believed that the amount of air is reduced by densely forming the tissue in the mortar due to fine particles of high-lime lime.

Table 9

3.2 Hardening mortar properties

Table 10 shows the experimental results of hardened mortar according to the ratio of natural organic lime and high-lime lime materials.

Table 10

(1) Compressive strength

4 and 5 are graphs showing the change in mortar mixing ratio and the compressive strength of the curing agent material combination ratio. First, Figure 4 is a graph showing the compressive strength according to the material combination ratio in the composition ratio FC: BS = 5: 5 first curing agent at a mortar ratio of 1: 5. In the case of the 3-day-old compressive strength, the material combination ratio of natural organic lime and high-earth lime in FIG. 4 was 2.26 MPa at H: G = 2.5: 7.5, showing the best strength enhancing effect. However, in the case of 7 days of age and 28 days of age, the material combination ratio of natural organic lime and high-lime lime is H: G = 5: 5 to 4.49 MPa, 9.68 MPa, and the material combination ratio H: G = 2.5: 7.5. Showed. In addition, when the composition ratio of the curing agent at the mortar compounding ratio 1: 5 was FC: BS = 7: 3, it showed better strength than the previous binder composition ratio. In addition, Figure 5 is a graph showing the compressive strength according to the mortar compounding ratio 1: 3, curing agent composition ratio and material combination ratio. First, the composition ratio of the curing agent is 1: 3 in the mortar mixing ratio of 1: 3, and the composition of the blast furnace slag is 7: 3, and the material combination ratio is excellent when mixing natural organic lime and high-earth lime 5: 5 at 21.75MPa at 28 days of age. Intensity expression was indicated. In the case of initial strength, hydration products such as Type II CSH and Ca (OH) ₂ are generated according to the acceleration of hydration reaction by increasing the surface area of high-powder fine particle cement (FC) in contact with H ₂ O and contained in high-lime lime. In the case of magnesium hydroxide (Mg (OH) 2), which is a hydration product of magnesium oxide (MgO), it is used as an alkali stimulant to destroy the impermeable film of the blast furnace slag fine powder latent hydraulic reaction, Si ⁴ + and Al ³ + ions, especially Al ³ + Hydration of 2CaO · Al ₂ O ₃ · SiO ₂ glass proceeds because ions are eluted. Therefore, it is judged that the strength increased by curing while forming the calcium silicate hydrate (CSH) by combining the eluted silicate (SiO ₂ ) and calcium oxide (CaO).

(2) Flexural strength

6 and 7 are graphs showing the flexural strength of each material combination according to the change in mortar mixing ratio and the curing agent composition ratio. As shown in Fig. 6, in the case of mortar compounding ratio 1: 5, the composition ratio of the curing agent: fine particle cement: blast furnace slag FC: BS = 5: 5, as the combination ratio of natural organic lime (H) increased, the strength increased. In addition, the composition ratio of the curing agent showed a tendency of the composition ratio of the curing agent to the fine particle cement: blast furnace slag 5: 5 even in the fine particle cement: blast furnace slag 7: 3, and it was impossible to measure the flexural strength at 3 days of age in all formulations. This is because the amount of powder decreases due to an increase in the proportion of fine aggregates, so it is judged that the hydration reaction is delayed and thus insufficient to express the initial strength. Figure 7 shows the strength increase as the curing agent combination material is biased with natural organic lime (H) in the composition ratio of curing agent FC: BS = 7: 3, FC: BS = 5: 5 in the case of mortar compounding ratio 1: 3, 3 days of age The flexural strength showed strength. This is considered to be due to the acceleration of the hydration reaction because the amount of powder increases due to the decrease in the proportion of fine aggregate.

(3) SEM photograph of 7 days of age

8 to 12 show SEM photographs according to the material combination ratio of the curing agent at 7 days of age. First, in the case of FIGS. 8 to 10, the initial hydration product is a SEM photograph according to the material combination ratio of natural organic lime (H) and hard lime (G) of H: G = 10: 0, 7.5: 2.5, 5: 5 It can be seen that Ettringite, Ca (OH) ₂ crystals and CSH hydrate were produced. In addition, FIGS. 11 and 12 are hydration products Ca (OH) ₂ of natural organic lime and Mg, which is a hydration product of MgO of high-lime lime, according to SEM photograph analysis at a combination ratio of H: G = 2.5: 7.5, 0:10. (OH) ₂ was generated and coexisted, and it was confirmed that a large number of two-dimensional network or honeycomb-shaped Type IIC-SH and Ettringite were generated.

(4) SEM photograph of 28 days of age

13 to 17 shows the SEM picture of the material composition ratio at the time of composition with the composition ratio of fine particle cement: blast furnace slag 7: 3 at the age of 28 days. First, FIG. 13 and FIG. 14 are SEM photographs of the curing agent combination ratio H: G = 10: 0, 7.5: 2.5 to confirm hydration products such as needle-like Ettringite and Ca (OH) 2. However, in the case of FIG. 15, unlike H7, age, H: G = 5: 5, magnesium oxide Mg (OH) ₂ , two-dimensional network type II CSH, and needle-shaped Ettringite were generated and confirmed the tight structure. 16 and 17 show SEM photographs of the material mixing ratio H: G = 2.5: 7.5, 0:10 at 28 days of age. It can be confirmed that Ca (OH) ₂ and Ettringite were formed. In addition, Ca (OH) ₂ , which is a hydration product of calcium oxide (CaO), and Mg (OH) ₂ , which is a hydration product of magnesium oxide (MgO) of high-lime lime, and a two-dimensional network or honeycomb type Ⅱ CSH are produced. I could confirm.

(4) Analysis of cumulative pore distribution (Porosimeter)

18 and 19 are diagrams showing the distribution of pores up to a size of 0.001 to 0.1 μm on 7 and 28 days of age according to the curing agent combination ratio. Overall, cumulative work volume tended to decrease as age increased. In addition, it was found that the amount of pores of about 0.05 µm and 0.8 µm in diameter decreased and the amount of finer pores increased. This is because pores of 0.05 µm or less are the size of gel pores and capillary pores, which is closely related to the strength of concrete. Since it is known to have a, it is considered to be a cause due to an increase in compressive strength. Accordingly, H: G = 5: 5, H: G = 7.5: 2.5 compared to H: G = 10: 0, H: G = 10: 2.5 and H: G = 0: 10. According to the graph analysis of the cumulative pore distribution of the work, the cumulative pore volume of about 0.001 µm or more was decreased by about 20%.

(5) XRD analysis

FIG. 20 shows the results of XRD analysis according to the material mixing ratio when the composition ratio of the curing agent of the mortar mixing ratio 1: 3 is the fine particle cement: blast furnace slag 7: 3. For the quantitative analysis of components, the results of XRD analysis are presented. First, hydration products Mg (OH) ₂ , 2Theta 38.02 °, 18.09 °, and 47.12 ° of MgO contained in high-lime lime, and the hydrated organism Ca (OH) 2 of CaO were 2Theta 33.94 °, 18.9 °, 47.12 It was confirmed that it appeared at °. In addition, in the case of SiO ₂ found in sand or quartz contained in the soil, K ₅ Ca ₈ (Si ₆ O), a chemical component that forms rocks due to the fine aggregate of mortar at 2Theta 21.98 °, 27.20 °, 23.84 °, and 15.14 ° ₁₅ ) ₂ (Si ₂ O ₇ ) Si ₄ O ₉ (OH) · 3 (H ₂ O) occupies a significant portion, and this chemical composition is the main chemical element of 12.88% K ₂ O natural organic lime and particulate cement It is composed of 24.53% CaO and 59.14% SiO ₂ 0.39% H 3.45% H ₂ O, the main chemical components of rock.

In Example 1, as described above, for the purpose of deriving the optimal amount of natural organic lime and high-lime lime from blast furnace slag-based mortar using natural organic lime and high-lime lime, the overall characteristics of mortar according to the mixing ratio of each material are examined. And, through the analysis of the mortar's fluidity and strength performance and microscopic analysis, it was intended to derive the optimal combination of natural and natural lime and high-lime lime. The contents are summarized as follows.

1) Due to the flow characteristics of the uncured mortar, in the case of the mixing ratio of the natural organic lime according to the material mixing ratio of the natural organic lime and high-earth lime, the float tended to increase somewhat. In addition, in the case of high-lime lime, it exhibited a low float compared to 100% of natural organic lime due to the increase in viscosity according to the high degree of powder, and it was judged that the mixing ratio of natural organic lime and high-lime lime would be effective in terms of fluidity when replacing each 50%. do.

 2) As a result of the air mass characteristics, the tendency of the increase in the mixing ratio of the natural organic lime increased, and the tendency of the decrease in the air mass increased as the substitution rate of the high-lime lime increased.

3) As a strength characteristic of hardened mortar, first, the compressive strength of the blend using 50% of the material mixing ratio each was higher than that of the mortar blend using the natural organic lime and high-lime lime at a material mixing ratio of 100%. , First, if the substitution rate of natural organic lime is biased, it is judged that the strength decreases due to the large amount of pores. When natural organic lime and high-lime lime are mixed at 50%, the hydration products of natural organic lime are Ca (OH) ₂ and Mg (OH) _{2, which} is hydration products of high-lime lime, as an alkali stimulating agent, and react the potential hydraulic reaction of blast furnace slag. It is believed that the hydration reaction was promoted to enhance the strength. In the case of mixing 50% of natural organic lime and high-lime lime, the combination used showed a compressive strength measurement of about 21 MPa, and showed a higher compressive strength than other formulations.

4) During microscopic analysis of hardened mortar, SEM photo analysis by material composition ratio of curing agent 7 days of age by SEM photo analysis showed that H: G = 10: 0, 7.5: 2.5, 5 of natural organic lime (H) and high-grade lime (G) In the case of the SEM photograph according to the material combination ratio of 5, it was confirmed that Ettringite, Ca (OH) ₂ crystals, and CSH hydrate were produced as the initial hydration product. In addition, at a combination ratio of H: G = 2.5: 7.5, 0:10, the hydration product of natural organic lime Ca (OH) ₂ and Mg (OH) ₂ of hydration product by MgO of high-lime lime according to SEM photograph analysis It was confirmed that it was coexisting, and a large number of two-dimensional reticular or honeycomb Type IIC-SH and Ettringite were generated. Composition ratio of curing agent at age of 28 days Particle cement: blast furnace slag 7: When composition is made by SEM image by material combination ratio, curing agent combination ratio H: G = 10: 0, 7.5: 2.5 SEM image of needle-shaped Ettringite and Ca (OH) Hydrate products such as ₂ can be confirmed. In addition, H: G = 5: 5, magnesium oxide Mg (OH) ₂ , a two-dimensional network type II CSH and needle-like Ettringite were produced and confirmed the tight structure.

5) XRD analysis results for quantitative analysis of the composition of hardened mortar. First, hydration products Mg (OH) ₂ , 2Theta 38.02 °, 18.09 °, 47.12 ° of MgO contained in high-lime lime, and hydrated organism Ca (OH) ₂ of calcium oxide (CaO) 2Theta 33.94 °, 18.9 °, it was confirmed that it appeared at 47.12 °. In addition, in the case of SiO ₂ found in sand or quartz containing soil, K ₅ Ca ₈ (Si ₆ O ₁₅ ) ₂ (Si ₆ O ₁₅ ) ₂ (Si ₆ O ₁₅ ), which is a chemical component that forms rocks at 2Theta 21.98 °, 27.20 °, 23.84 °, and 15.14 ° ₂ O ₇ ) Si ₄ O ₉ (OH) · 3 (H ₂ O) occupies a significant portion, and the chemical composition of this is 12.88% K ₂ O 24.53% CaO and rocks, which are the main chemical elements of natural organic lime and particulate cement. It is composed of 59.14% SiO ₂ 0.39% H 3.45% H ₂ O, which is the main chemical component.

6) As a result of the experiment of cumulative pore distribution by age, the overall cumulative pore volume tended to decrease as the age increased. In addition, it was found that the amount of pores of about 0.05 µm and 0.8 µm in diameter decreased and the amount of finer pores increased. This is because pores of 0.05 µm or less are the size of gel pores and capillary pores, which is closely related to the strength of concrete. Since it is known to have a, it is considered to be a cause due to an increase in compressive strength. Accordingly, H: G = 5: 5, H: G = 7.5: 2.5 compared to H: G = 10: 0, H: G = 10: 2.5 and H: G = 0: 10. According to the graph analysis of the cumulative pore distribution of the work, the cumulative pore volume of about 0.001 µm or more was decreased by about 20%.

 In summary, when natural organic lime and high-lime lime are used by replacing the mixing ratio of each material with 50%, it increases in terms of fluidity and strength in mortar, and is effective in the strength expression of blast furnace slag, and the mixing ratio of material 50 % Compression strength was confirmed in the formulation. Therefore, considering the performance aspect, a combination of 50% natural organic lime and 50% high-lime lime was considered to be effective and was selected as the optimal mixing ratio. If smooth supply and demand of natural organic lime is not possible, 75% of natural organic lime 25% of natural organic lime The use of is also expected to be possible.

<Example 2> Preparation of blast furnace slag concrete including natural organic lime and high-earth lime and analysis of the properties of the concrete

In Example 1, for the purpose of deriving the optimum mixing ratio of natural organic lime and high-lime lime from blast furnace slag-based mortar using natural organic lime and high-earth lime, the overall properties of mortar using each mixed material are reviewed, and mortar Through the analysis of the fluidity, strength, and microscopic analysis, the optimum formulation of 쳔 soft organic lime and high-lime lime in terms of performance was sought. Accordingly, the material mixing ratio in the composition ratio of the fine particle cement: blast furnace slag 7: 3 was selected as the optimal mixture by mixing 5 to 5 with natural organic lime and high-earth lime.

 Therefore, in this Example 2, the overall characteristics of the concrete standards for the development of a concrete pavement hardener based on the derived maximum mixing ratio were analyzed, and the compressive strength, flexural strength, compressive strength (100cycle), and sliding after freezing and thawing in hardened concrete Through the resistance and waste process test, we will finally select the curing agent substitution rate that satisfies the quantitative value of this study.

Table 11 shows the experimental plan for the development of a hardened concrete paver using natural organic lime and high-lime lime, and Table 12 shows the formulation. First, the water content was planned to be ω 18%. The composition of the binding material was calculated as the composition of the fine particle cement: blast furnace slag 7: 3 as the mass ratio to the unit binding amount based on 3 types of blast furnace cement, and in the case of natural organic lime and solid earth lime, the mass ratio to the unit binding amount is 0,5 %. As an experimental matter, the experimental plan was to measure the compressive strength, flexural strength, compressive strength after freeze-thaw (100cycle), slip resistance, and waste process test in hardened concrete.

Table 11

Table 12

1. Materials used

(1) Natural organic lime

The organic lime used in this experiment was a domestic D company, and its physical and chemical properties are shown in Table 13.

Table 13

(2) Goto lime

As for the high-lime lime used in this experiment, domestic D company products were used, and the physical and chemical properties are shown in Table 14.

Table 14

(3) Masato

The masato used in this experiment was a domestic D company, and its physical and chemical properties are shown in Table 15.

Table 15

(4) Particulate cement

As the binder used in this experiment, the product of domestic A was used for the particulate cement, and the physical and chemical properties are shown in Table 16.

Table 16

(5) Blast furnace slag

As the binder used in this experiment, three types of blast furnace slag fine powder were used in the domestic company A, and the physical and chemical properties are shown in Table 17.

Table 17

2. Experimental method

(1) Concrete mixing

Concrete mixing is carried out in the order of FIG. 21 using a twin shaft mixer. That is, the mixer was put into a fine aggregate of 70L capacity, natural organic lime, fine particle cement, blast furnace slag and binder and fine aggregate, and subjected to dry rain at low speed (20 rpm) for 30 seconds. Then, after adding water and emptying for 60 seconds at medium speed (30 rpm), a mixture was added to mix and discharge at high speed (40 rpm) for 90 seconds.

(2) Unconsolidated concrete experiment

Due to the nature of the unconsolidated concrete, due to the nature of the soil-paved concrete product, it is a low W / C, so it is impossible to measure the slump and slump flow due to the minimum formable fluidity.

(3) Molding and curing of the specimen

The specimen for compression strength and flexural strength test is manufactured using molds of 100 × 200 mm (compressive strength) and 100 × 100 × 400 mm (flexural strength) according to the KS F 2405 standard, and the tensile strength test is based on the domestic KS F 2408 standard. It is manufactured in accordance with the standards given in. The curing of this product is carried out in accordance with the planned age in a constant temperature and humidity room at 20 ± 2 ℃ and 60% humidity.

(4) Compressive strength test

Compressive strength is 100 × 200mm and manufactured according to KS F 2403 regulations. Measured using 3 MN U.T.M in accordance with KS F 2405 regulations at a predetermined age.

(5) Bending strength test

The flexural strength is 100 × 100 × 400mm and manufactured in accordance with KS F 2403 regulations. Measured using 3 MN U.T.M in accordance with KS F 2408 regulations at a predetermined planned age.

(6) Freeze-thawing test

The freeze-thawing test is carried out using a freeze-thawing test apparatus in the air freezing and submerging method of B corporation in KS F 2456 after curing under water for 14 days of age using a 100 × 100 × 400 mm prismatic mold. At this time, the freeze-thaw cycle alternately lowers the temperature of the specimen between 2 hours and 4 hours from 4 ° C to -18 ° C, and then increases from -18 ° C to 4 ° C. The freeze-thawing test is conducted up to 100 cycles, and during the test, the specimen is taken out of the test tank and the attached impurities, etc., are washed and removed with water.

The test body after 100 cycles of freeze-thawing test is to measure the compressive strength through the compressive strength test method.

(7) Slip resistance test of road surface

In the case of the absorption rate test, the weight of the pendulum including the slider is (1,500 ± 30) g by taking two test specimens manufactured in accordance with the regulations of KS F 2375 with a size of at least 90 × 150 mm. It is (410 ± 5) mm from the center of vibration to the center of gravity of the pendulum, and measures the energy loss that occurs when rubbing the road surface against the test surface of a rubber slider.

(8) Waste process test

These waste process test standards (hereinafter referred to as "process test standards") are necessary to maintain the accuracy and uniformity of measurement in measuring the properties and pollutants of wastes in accordance with Article 6 of the Act on Testing and Inspection in the Environmental Field. For the purpose of stipulating, it was conducted in accordance with the Ministry of Environment Notice No. 2015-50 ('15 .4.14).

3. Experimental results and analysis

Due to the characteristics of the unconsolidated concrete, it was confirmed whether the molding was possible through visual observation according to the characteristics of the product, in accordance with the low W / C ratio and securing the fluidity of the minimum formability. There was no particular problem in formability as a result of visually judging whether or not molding was possible with the properties of unconsolidated concrete and confirming the surface shape of the manufactured product.

3.1 Hardened concrete properties

(1) Compressive strength and flexural strength

Table 18 and Table 19 show the experimental results of the cured concrete according to the substitution rate change of the development curing agent. Figure 22 shows the compressive strength by age of concrete according to the change rate of substitution of the development hardener. First of all, in order to compare the development hardener, the compression strength for parking lots of 18 MPa or higher was based on the quality and required performance of each type of soil concrete of SPS-KSCICO-001 shown in Table 20. Therefore, in the case of 20% and 25% of the substitution rate, it was less than the standard compressive strength of about 12.7 MPa and 16.32 MPa at 28 days of age. However, in the case of the curing agent substitution rate of 30%, the strength was higher than the standard compressive strength at about 21 MPa on the 7th day of age, and the compressive strength at 28 days of age was about 25 MPa. FIG. 23 shows the flexural strength according to the curing agent substitution rate, and when comparing 3 MPa of SPS-KSCICO-001 with the same compressive strength, when the substitution rate was 30% or more, the intensity was higher than the reference value by about 3.1 PMa. As described above, as the hydration products of natural organic lime and high-lime lime are used as alkali stimulants in the latent hydraulic reaction of blast furnace slag, it is determined that the compressive strength is maximized by generating a large amount of ethrinite hydrate and calcium silicate.

Table 18

Table 19

Table 20

(2) Compressive strength after freezing and thawing

Tables 21 and 24 show the compressive strength after freezing and thawing of concrete according to the change of the curing agent substitution rate. First, the compressive strength was compared after freezing and thawing according to the curing agent substitution rate based on the quantitative target value of 20 MPa or more. At 20% and 25% of curing agent substitution rate, after 10 cycles of freeze-thawing, compressive strength measurements of about 10 MPa and about 13 MPa were shown, and in the case of substitution rate of 30%, compressive strength measurements of about 2 MPa higher than the reference value of 20 MPa. As shown above, it is judged that the strength is improved as a result of promoting the latent hydraulic reaction of the blast furnace slag, and it is determined that the resistance to freezing and thawing is increased due to the tight structure through the cumulative pore distribution.

Table 21

(4) Surface slip resistance and waste process test

Table 22 shows the quality and required performance of soil concrete of SPS-KSCICO-001 presented in Table 20 and the waste standards and development products of the Ministry of Environment waste process test. It is a graph showing the results of comparing the slip resistance of the road surface and the waste process test.

Table 22

In this Example 2, after preparing the soil forging concrete based on the derived maximum mixing ratio, comparative characteristics of the existing products and the standards of the developed soil pavement concrete are compared, and the compressive strength for the use of the development hardener, The flexural strength, the compressive strength after Tokyo melting, the sliding resistance of the road surface and the waste process test were reviewed, and finally, to develop an environmentally-reducing soil-paved concrete product using natural organic lime and high-earth lime, the contents were summarized as follows: Same as

1) First, we compared the product according to the substitution rate change of the developed product with the characteristics of the unconsolidated concrete. Due to the characteristics of all products, it is possible to form through slump and visual observation according to securing the low W / C ratio and minimum formability of fluidity. Was confirmed. As a result of confirming the surface shape of the manufactured product, there was no particular problem in moldability.

2) Due to the strength characteristics, the compressive strength tended to increase as the substitution rate of the developed product increased. In particular, the standard compressive strength was about 18 MPa for the 28th day of age, and for the developed product, the curing agent substitution rate was about 21 MPa at the 7th day of age for the 30% substitution rate, and the compressive strength was about 28th day. The strength was expressed at 25 MPa.

3) Compressive strength after freeze-thawing. In the case of existing products, after 20 cycles of freeze-thawing, the compressive strength was about 18 MPa.

4) As a result of road surface slip resistance and waste process test, when the curing agent substitution rate was more than 30%, the road surface slip resistance was 45 BPN, which was more than 5 BPN compared to the slip resistance of the standard road surface. .

Summarizing the above, the developed product of soil-paved concrete using natural organic lime and high-earth lime showed equivalent or higher performance than the existing performance, and the effect of cost reduction by about 20% by using industrial by-products and circulating resources Occurred. It has been shown that it is effective in recycling resources and reducing environmental loads different from existing products by giving the functionality of natural organic lime and high-earth lime.

The above has been described based on the preferred embodiment of the present invention, but the technical spirit of the present invention is not limited to this, and it is possible to carry out modifications or changes within the scope of the claims, and those skilled in the art to which the present invention pertains. It will be apparent to the applicant, and such modifications or changes will fall within the scope of the appended claims.

Claims (8)

Natural organic lime;
Goat lime; And
Blast furnace slag cement; hardener for soil-paved concrete containing. According to claim 1,
10 to 20% by weight of natural organic lime and goji lime; And
Blast furnace slag cement 80 to 90% by weight; hardener for soil-paved concrete, characterized in that it comprises a. According to claim 2,
Hardener for soil-paved concrete, characterized in that it comprises natural organic lime and goji lime in a weight ratio of 2: 8 to 8: 2. According to claim 3,
Hardener for soil-paved concrete, characterized in that it contains natural organic lime and goji lime in a weight ratio of 5: 5. According to claim 2,
The blast furnace slag cement is a curing agent for soil pavement concrete, characterized in that it contains 30 to 50% by weight of blast furnace slag fine powder. The method of claim 5,
The blast furnace slag cement is a hardener for soil-paved concrete, comprising blast furnace slag fine powder and fine particle cement in a weight ratio of 3: 7. A soil-paved concrete composition comprising the curing agent of claim 1. (a) compacting the ground to be packaged;
(b) laying and compacting the soil paved concrete composition of claim 7 on the ground; And
(C) curing the laid and compacted soil pavement concrete composition; dry soil pavement method comprising a.

Images