KR101182872B1 - Environmental-friendly high-strength permeable block and its manufacturing method - Google Patents

Abstract

The present invention relates to an environment-friendly high-strength permeable block using industrial by-products and low-grade limestone, and more particularly, to a permeable block comprising low-grade limestone, natural aggregates or recycled aggregates, binders and admixtures, low-grade limestone, Forming a powder by mixing the binder and the admixture, forming a paste having a clinker factor of 0.1 to 0.25 by adding water to the powder so that the water binder ratio is 10 to 20%, and natural to the paste It relates to a method for producing a permeable block having a porosity of 15 to 25% after curing by adding aggregate or recycled aggregate.

According to the present invention, the low-grade limestone discarded can be applied as the aggregate of the permeable block, so that the effect of replacing the natural aggregate and reducing the environmental pollution can be expected, minimizing cement components and alkali as a natural inorganic material without using organic admixtures. It can be expected to provide an eco-friendly permeable block without dissolution and express high compressive strength.

Pitcher Block, Porous Concrete, Eco-Friendly, Low Grade Limestone

Description

Environment-friendly high-strength permeable block and its manufacturing method using industrial by-products and low-grade limestone

The present invention relates to an environment-friendly high strength water permeable block using industrial by-products and low-grade limestone and a method for manufacturing the same.

Recently, the development direction of construction materials and construction methods has been progressed in the form of environmental load reduction and environmentally friendly development that minimizes the preservation of ecosystems and damage to the natural environment. Many construction materials have been developed and developed with the development of the industry, but the development of environmentally friendly environmental materials has not been achieved.

Most of the construction materials used today require watertight products that prevent rainwater from permeating, which is why rainwater does not return to the soil but flows into sewers, which is a major cause of flooding during the summer rainy season. In addition, it causes the depletion of groundwater and causes environmental damage such as adversely affecting the ecosystem that represents desertification of the city.

Therefore, the development of porous concrete (permeable block) having a large amount of continuous voids as an environmentally friendly material is urgently required, and the vegetation greening method, water purification method, depending on the permeability and particle size of the construction material by the continuous porosity of the porous concrete It is used for water-permeable packaging methods and sound absorption methods using sound absorbing and insulating properties of building materials.

For concrete materials called pore concrete, aggregates and cement paste of single grain size are mainly used. As single grain aggregate, JIS No. 5 crushed stone (13 to 20 mm), JIS No. 6 crushed stone (5 to 13 mm), and JIS No. 7 crushed stone (2.5 to 5 mm) are used. Some studies have also confirmed the use of lightweight aggregates.

In most studies, cement is commonly used in Portland cement. Among them, admixtures that are expected to improve the strength and symbiosis with living organisms, such as silica fume and fly ash, and admixtures with potential hydrophobic properties such as blast furnace slag fine powders and polymers. The study of low alkalinity using cement and neutral phosphate cement is also shown.

In addition, the use of recycled aggregates and the study of porous concrete by recycled cement for the recycling of concrete have been actively studied.

Most of the researches range from 10 to 50% by volume of aggregate and cement paste. In the past, the water binder ratio was in the range of 40-50%, but recently, due to the emergence of high-performance AE reducing agent, the water binder ratio is increasing in the range of 30% or less.

Aggregate is described in the materials used, and there is an example in which single-grained crushed stone is used and a small amount of aggregate or small aggregate is used.

On the other hand, Korea's total mineral reserves are estimated at 9.33 billion tons as of 2005, and non-metallic mineral reserves are 7.71 billion tons, accounting for more than 83% of the total minerals. Limestone minerals account for more than 75% of the nonmetallic minerals, which account for more than 75% of the nonmetallic minerals, based on the CaO content of 40% or more, 25m or more and 100m or more. The estimated reserves are estimated to be around 35 million tons in 173 mines.

Limestone resources are widely distributed mainly in Gangwon and Chungbuk areas, among which the high-grade limestone veins are concentrated in Danyang, Chungbuk. There are about 42 limestone mines in the entire Chungcheongbuk-do region, with reserves of about 270 million tons, accounting for 4.2% of the entire region.

In addition, limestones classified as high quality among domestic limestone resources are buried in order of 71.0% in Gangwon, 16.1% in Chungbuk, and 11% in Gyeongbuk, and the distribution of high and low grade limestone in Chungcheongbuk-do and Gangwon-do is found in each region. The relative proportion of high-grade and low-grade limestone is about half that in Chungcheongbuk-do, and about 87% in Gangwon.

Given the lack of high quality resources due to the indiscriminate development of high quality limestone resources in each mine, the situation has to be shifted to the low and medium level mining structure. Alternatively, the amount of limestone classified as waste resources is expected to grow exponentially year by year, and secondary problems arising from failure to deal effectively with it are also expected to be serious.

Table 1 and Table 2 below show the reserves of high-grade and low-grade limestone in Chungbuk, respectively.

TABLE 1 High Grade Limestone Reserves by Region

Mine name sausage elegance(%)
CaO Pulse width (M) Extension (M) Reserve amount (thousand tons) Provision of light
(1,000 tons) Confirmation calculation system Great Lake Seating (Samju) Goesan annual wind 52.5 50-100 500 537 537 375 Hanheung Yeonpung Goesan annual wind 54.7 25-70 600 179 179 125 Gold river Goesan annual wind 54.6 80-150 1,000 2,434 2,434 1,704 Revival Goesan Cheongan 54.7 60 350 20 20 14 Wooin Lime (Emerging) Goesan Cheongan 54.1 50-100 300 551 551 386 Baekwangyeocheon Danyang Gagok 53.4 30-40 1,300 733 1,312 2,045 1,578 Large songs Danyang Maepo 53.9 100-130 700 48,813 48,813 34,169 White light Danyang Maepo 54.7 100-250 750 1,641 4,744 6,385 5,272 Baekwang Youngcheon Danyang Maepo 54.5 30-50 1,000 1,341 1,341 1,072 Songcheon A Danyang Maepo 53.1 100-150 800 1,365 1,365 1,092 Gwangjin Danyang Fishing Stream 54.3 30-80 800 2,583 2,583 2,066 Daesung Danyang Danyang Fishing Stream 54.4 30-60 1,600 940 5,712 6,652 5,415 Stone bridge Danyang Fishing Stream 53.9 40-50 1,500 2,419 2,419 1,693 Former mountain Danyang Viscount 53.1 10-50 1,000 3,350 3,350 2,345 Hundred mountains Danyang Yeongchun 55.3 30-80 1,600 3,353 3,353 2,347 Korean Lime Okcheon Cheongsan 53.3 30-70 500 767 767 536 Woojin Sungjin Jecheon Venus 54.3 100-150 800 2,577 2,577 2,061 Korea Lime Jecheon Venus 54.7 100-130 400 2,498 2,498 1,998 Daesung Jecheon Jecheon Doohak 53.7 30-100 12,600 12,949 31,632 44,581 33,796 Yong Jung Jecheon Doohak 53.1 20-80 2,600 1,558 7,028 8,586 6,320 Specification Jecheon Doohak 52.8 30-200 2,300 8,172 8,172 6,532 Song Hak Jecheon Songhak 54.4 20-160 2,300 611 3,702 4,313 3,140 Ah Jin Jecheon Viscount 54.7 20-40 1,000 271 271 190 Rice wine Petition Gaduk 54.6 100 800 2,040 2,040 1,632 Wu days Petition inquiry 54.1 70-80 700 605 605 423 system 25 mines 18,432 138,005 156,437 116,281

TABLE 2 Low Grade Limestone Reserves by Chungcheongbuk-do Region

Mine name sausage elegance(%)
CaO Pulse width (M) Extension (M) Reserve amount (thousand tons) Provision of light
(1,000 tons) Confirmation Estimate system Guangdeok Goesan Moonlight 49.7 30-40 500 463 463 324 Intestinal cancer Goesan Cheongan 51.8 60 250 374 374 261 Danyang Lime Danyang Danyang 47.0 300 700 2,541 2,541 1,778 Sungshin Labor
Hemp labour Danyang approx 49.2 50-80 2,00 526 23,750 24,276 16,625 Great river Danyang approx 50.3 100-150 1,500 15,700 15,700 10,990 Shin Guang Danyang Maepo 46.3 500 2,000 3,844 3,844 2,691 Hyundai Danyang Danyang Maepo 47.4 500-600 1,500 30,632 30,632 21,442 Young Dong Youngdong Haksan 51.2 180 230 1,988 1,988 1,590 Young Chun Danyang Yeongchun 42.8 200 1,800 7,392 7,392 5,174 Ssangyong (Samhwa) Danyang Aptitude 51.8 100-450 800 24,861 24,861 17,402 Half stone Youngdong Haksan 53.0 130 550 980 980 686 Young Dong Youngdong yellow 46.0 50-90 400 97 97 97 Samfeng Youngdong yellow 45.5 120 250 480 480 336 Union Taesung Okcheon Cheongseong 50.3 100-160 2,500 3,664 3,664 2,565 freedom Jecheon Daerang 49.4 50-150 1,000 2,883 2,883 2,018 Four I Jecheon Songhak 40.4 100 800 1,112 1,112 778 Road shoes Jecheon Songhak 26.7-47.0 100-200 600 1,418 1,418 992 system 17 mines 526 122,179 122,705 85,719

As shown in Tables 1 and 2, the high-grade limestone reserves in Chungbuk are estimated to be about 150 million tons, but the low-grade limestone is also about 120 million tons, which is a strategic stockpile and low-grade resource of high-quality resources. Measures for efficient use of the system should be preceded, and domestic resource acquisition policies should be supported.

The low-grade limestone resources, which are generated in large quantities in domestic limestone mines each year, cannot be efficiently handled, which indicates a serious problem that occurs when the mine is left unattended or left unattended. At present, most domestic mines use low quality or waste resources or by-products generated as wastes in the process or at low value added to the mines and are left unattended without any countermeasures. There is a situation.

In fact, the amount of low-grade limestone resources generated annually in nearby areas such as Danyang, Jecheon, and Yeongwol is estimated to be about 7-8 million tons, and it is not possible to process them efficiently, resulting in very low added value such as cement, aggregate and landscape stone. / Ton) As it is used as a product, it is necessary to diversify its use through technology development for high value-added.

In addition, in the current production structure, it is urgent to seek a transition to a high value-added industrial structure on the basis of the improvement of added value of limestone through the high purity of low and low-grade limestone, stabilization of supply and demand of raw materials, and self-sufficiency of raw materials.

The present invention intends to utilize low-grade limestone, which occurs in large quantities of more than 6-7 million tons annually in Jecheon / Danyang, Chungbuk, as a new aggregate material for permeable blocks (porous concrete) and to develop eco-friendly civil engineering materials. The purpose of this study is to provide a permeable block that shows optimum physical properties by examining the physical properties for the formulation and extraction for the development of a permeable block using alternative raw materials.

In particular, as a binding material that determines the strength of the permeable block, it is intended to achieve high compressive strength by ionic aggregation reaction, pozzolanic reaction, and latent hydraulic reaction using only natural inorganic materials without minimizing cement components and adding organic admixture such as resin. In order to provide a permeable block free from alkali elution.

As an example for achieving the above object, the present invention includes a low-grade limestone with a CaO purity of 35 to 45%, natural aggregate or regenerated aggregate having a particle size of 3 to 25 mm, binder and admixture, water binder ratio of 10 to 25 % And clinker factor of 0.1 to 0.25 to provide a permeability block having a continuous porosity of 15 to 25% after curing.

The low-grade limestone is preferably included in the range of 85 to 95% by weight of the total weight of the permeable block.

It is preferable that the binder has a blast furnace slag substitution rate of 10 to 30% with respect to cement.

As the admixture, it is preferable to use a lignin-based water sensitizer.

The paste preferably has a flow of 145 to 155 mm.

As another example for achieving the above object, the present invention is a process of forming a powder by mixing a low-grade limestone with a CaO purity of 35 to 45%, a binder and a mixed material, water to the water binder ratio of 10 to 20% to the powder Adding and forming a paste having a clinker factor of 0.1 to 0.25, and mixing and adding a natural aggregate or recycled aggregate having a particle size of 3 to 25 mm to the paste such that the porosity is 15 to 25% after curing. It provides a method for producing a permeable block comprising a step of curing after one.

According to the present invention, it is excellent in walking even at the time of excellence, can reduce the occurrence of global warming phenomenon for heat island phenomenon, can reduce the occurrence of urban flood due to non-permeable surface, and depletion of groundwater due to lack of water It can be gradually prevented and can provide a permeable block to prevent non-point pollution caused by the non-permeable surface.

In addition, according to the present invention, by using the low-grade limestone as a substitute material for the cement, it is possible to improve the resource utilization and to reduce the CO ₂ generation due to the reduction of clinker factors.

In addition, it is expected that the following effects can be obtained when the amount of CO ₂ reduction according to the low-grade limestone and cement component replacement material utilization is calculated.

That is, by using limestone powder, blast furnace slag, silica fume, and gypsum as a substitute for cement, the amount of CO ₂ generated in the production of existing cement is reduced (830 kg CO _{2 is} generated in the production of cement 1 ton) and CO ₂ due to cement replacement Effects such as generation reduction (reduction of 8.3kg CO ₂ generation by replacing cement 1% with Busan resources) can be achieved.

In addition, the reduction of the clinker factor (CF) is expected to continue to reduce CO ₂ emissions, and it is expected to increase carbon credits in proportion to the cement replacement ratio (KRW 36,500 / ton). The carbon tax is expected to be reduced (approximately 20% of the cement replacement rate at W3,464 / ton).

Hereinafter, an example of the present invention will be described in detail with reference to Examples, Experimental Examples and drawings, but the present invention is not limited by the following Examples and drawings.

Experimental Example 1. Physical property test of porous concrete

In order to investigate the feasibility of using a limestone mine as a porous concrete aggregate for low-grade limestone, this study selects the aggregate type and particle size based on the comparative experiments on the physical performance of the porous concrete by aggregate type and aggregate particle size. We tried to examine the physical experiments by adding cement, which acts as a paste, by replacing blast furnace slag with industrial waste.

1) Experiment Design

As shown in the following Table 3, low-grade limestone and natural aggregates are divided into 4 ~ 8mm and 14 ~ 25mm for each particle size.In the case of natural aggregates, aggregates having a particle size of 8mm or more are difficult to supply. The experiment was performed with only one particle size of 4 ~ 8mm. In addition, the blast furnace slag (hereinafter referred to as "BFS") for the cement paste was replaced according to the amount of each added, and the possibility of recycling the slag was examined in parallel.

TABLE 3 Experimental factor and level

division Experimental factor Experimental level Experiments Series I
(Mining waste-rock) 4 to 8 mm
14 to 25 mm  BFS 0, 25, 50, 75% 8 Series II
(Natural aggregate)   4 to 8 mm  BFS 0, 25, 50, 75% 4

2) Experimental material

① Cement

The cement used in this experiment was one common Portland cement produced by A company in Korea, and its chemical properties are shown in Table 4 and Table 5 below.

[Table 4] Chemical Properties of Cement

Cement Type LoI MgO K ₂ O Na ₂ O Sulfuric anhydride (SO ₃₎ Remarks When C ₃ A <8% C ₃ A> 8% One kind of normal
Portland cement 3.0 or less 5.0 or less - - 3.0 or less 3.5 or less KS Standard 0.54 2.32 0.95 0.15 - 1.87 Test result

[Table 5] Physical Properties of Cement

Item unit KS standard Test result Powder Specific surface area Cm 2 / s? G Over 2,800 3,401 Stability
(Autoclave Expansion) % 0.8 or less 0.08 Setting time
(Gillmore) Candle texture minute 60 or more 205 Termination time below 10 4:45 Compressive strength 3 days robbery kg / ㎠ 130 or more 222 7 days robbery kg / ㎠ 200 or more 311 28 days strength kg / ㎠ Over 290 406 importance - - 3013

② admixture

As the admixture used in this experiment, a domestic naphthalene-based high performance water reducing agent was used, and the chemical properties thereof are shown in Table 6 below.

[Table 6] Chemical Properties of Admixtures

Admixture Type importance type color chief ingredient toxicity Naphthalene system 1.1 Liquid bitumen 1.Sodium Salt of Naphthalen Sulfonate
2.Calcium salt of Ligno Sulfonate system
3.Sodium Gluconate System radish

③ aggregate

Aggregates used in this experiment are mine waste / natural aggregates, and the physical properties of each aggregate by particle size are shown in Table 7 below.

[Table 7] Physical Properties by Aggregate Size

Aggregate Type Aggregate dimensions
(mm) Performance rate
(%) Porosity
(%) Unit weight
(Kg / ℓ) importance Remarks Mine waste 4 to 8
14-25 60
57 40
43 1.57
1.62 2.84
2.84 Danyang-gun Fishing Sangcheon
(Company D) Natural aggregate 4 to 8 65 35 1.61 2.49 Jecheonsan, Chungbuk

④ Blast furnace slag

The blast furnace slag used in this experiment was used blast furnace slag of Korea K company, the physical and chemical properties are shown in Table 8 below.

[Table 8] Physical and chemical properties of blast furnace slag

density Specific surface area
(Cm 2 / g) Activity index (%) Flow value ratio
(%) Oxidation
magnesium
(%) three
Sulfur oxide
(%) Intensity
outage
(%) chloride
ion
(%) basicity 7 days 28 days 91 days 2.90 4,450 78 108 125 101 4.30 0.32 0.02 - 1.81

3) Experimental Blend

The experiment was carried out by dividing the series I and series II by aggregate type as shown in the following Table 9 and Table 10, and the addition of blast furnace slag was calculated by 0, 25, 50, 75% compared to the cement paste for each particle size and added with substitution. (置換 添加)

[Table 9] Experimental Table for Mine Waste-rock

Series I
(Mining waste-rock) BFS
Substitution rate
(%) W / C
(%) Volume (ℓ / ㎥) Weight (㎏ / ㎥) Water reducing agent
(g) W Binder G Air W Binder G C BFS 4 ~ 8mm 0 25 67 85 649 200 67 268 0 155 1% of cement 25 201 67 50 134 134 75 67 201 14-25 mm 0 25 47 59 644 250 47 186 0 1746 25 201 67 50 134 134 75 67 201  ※ Specific gravity: C (3.15), G (2.71)

[Table 10] Experimental Table of Natural Aggregate

Series II
(Natural aggregate) BFS
Substitution rate
(%) W / C
(%) Volume (ℓ / ㎥ Weight (㎏ / ㎥) Water reducing agent
(g) W Binder G Air W Binder G C BFS 4 ~ 8mm 0 25 67 85 649 200 67 268 0 1557 1% of cement 25 201 67 50 134 134 75 67 201  ※ Specific gravity: C (3.15), G (2.40)

4) Experiment Method

Experimental specimen production

The experimental apparatus used for this experiment was a vibration press molding machine, the size of the mold was 350mm × 300mm × 100mm.

Test Methods

① Test body production

After curing in a wet curing tank for 24 hours after the above conditions, the specimen of 350mm × 300mm × 100mm was cut into 9 equal parts using a cutter to 100mm × 100mm × 100mm as shown in FIG.

② compressive strength

The compressive strength of the porous concrete was measured using the digital compressive strength tester (20ton) after the maximum load was measured according to the compressive strength test method of KS F 2405 concrete.

σc = (kgf / ㎠)

Where σ c is the compressive strength (kgf / cm 2), P is the maximum load (kgf), and A is the cross-sectional area of the specimen (cm 2).

③ porosity

1. The volume V1 of the specimen is calculated in advance.

2. Harden the porous concrete in the test container and demold it, and after carrying out specimens in water for 24 hours or more, measure the weight in water W1. At that time, turn the specimen in water and remove the air sufficiently so that there is no residual air in the specimen.

3. Measure air weight 자연 2 with the specimen in the dry condition after 24 hours at 20 ± 2 ℃ and 60% relative humidity.

The porosity A (%) of porous concrete is calculated by the following formula.

A = [1-(W2-W1) / V1] × 100

Here, A is the total porosity and continuous porosity of concrete, Ｖ1 is the volume of the specimen, 수 1 is the weight of the specimen, Ｗ2 is the weight (for the total porosity) and constant weight (for continuous porosity) after 24 hours of natural standing. to be.

④ Unit weight

The unit volume weight of the porous concrete specimen for compressive strength was calculated by the following equation.

ＵW = W / V (kg / ㎥)

Where UW is the unit volume weight (kg / m 3), W is the specimen weight (kg), and V is the specimen volume (m 3).

(C) Experimental results

Table 11 and Table 12 show the results of compressive strength (kgf / cm 2), porosity (%), unit volume weight (g / cm 3) by particle size according to blast furnace slag substitution rate for each aggregate type.

[Table 11] Compressive strength by dimension according to aggregate type

Kinds size
(mm) Compressive strength (kgf / ㎠) 7 days a year 14 days of age 28 days old 0% 25% 50% 75% 0% 25% 50% 75% 0% 25% 50% 75% Mine waste 4 to 8 131 142 127 105 106 129 95 120 118 106 98 103 14-25 58 58 69 65 40 38 46 77 57 67 81 72 Natural aggregate 4 to 8 131 101 134 108 143 114 145 121 177 114 102 143

[Table 12] Porosity by Aggregate

Aggregate Type
(mm) Mine waste Natural aggregate 4 to 8 14-25 4 to 8 0% 25% 50% 75% 0% 25% 50% 75% 0% 25% 50% 75% Porosity
(%) 22 21 25 23 32 31 29 29 14 20 19 15

1) Experimental Results and Discussion by Aggregate Type and Particle Size by Addition of Blast Furnace Slag

As shown in FIGS. 2 to 8, the compressive strength tendency according to age according to the blast furnace slag substitution rate for each aggregate type showed that the strength of the mine waste rock 4-8mm aggregates was increased as the age passed, regardless of the substitution of BFS. It showed a tendency to decrease and 14 ~ 25mm aggregate was confirmed long-term strength expression. In the case of natural aggregate, strong gravel showed excellent high long-term compressive strength at 75% of 4 ~ 8mm aggregate and substitution rate.

During the process of forming a gel film in the process of hydration of cement, a dormant period occurs, which is a state in which the hydration reaction is stopped due to film formation.

In the experiment mixture, blast furnace slag is added and reacted. The blast furnace slag is latent hydrophobic, and when contacted with water, forms a dense impermeable acid film on the surface of the slag particles, and strong alkali is supplied for continuous reaction and the film is destroyed. When the coating is broken, dissolution starts from the surface of the slag, insoluble matter is generated, and curing of the slag starts.

It is thought that the strength of the cement at 14 days is lowered as the above-mentioned combination of cement and blast furnace slag is formed in the rest of cement and impermeable acidic film formation of blast furnace slag.

Although the resting period is slower than when using ordinary ordinary Portland cement, calcium hydroxide (Ca (OH ₂ ) is produced as a reactant in the cement after the resting period of cement, which destroys the impermeable acid film of blast furnace slag. It is considered to be a cause of enhancement.

2) Experimental Results and Discussion on the Relationship between Compressive Strength, Unit Volume Weight and Porosity

9 to 10 show the correlation between the compressive strength and the unit bulk weight and porosity according to the particle size of each aggregate, and FIGS. 11 and 12 show the correlation between the unit bulk weight and the mine waste rock of 4 to 8 mm aggregate. At the same particle size of natural aggregates, the coarse grains showed low compressive strength and high compressive strength (kgf / cm2) .In the case of mine waste rock 14 to 25mm aggregates, the compressive strength was lower than that of 4 to 8mm specimens. It was found that the particle size of was large enough to have a high void in the specimen.

Experimental Example 2. Evaluation of Eco-friendly Permeable Block Binder

Instead of ordinary portland cement, which is a somewhat energy-intensive type, a study on the property characteristics of alternative use of industrial by-products was conducted to examine the possibility of producing porous blocks of the same level or higher.

1) Experimental method

In this experimental example, the factor of the Clinker Factor (CF) was determined by adjusting the cement content during powder blending according to the characteristics of the permeation block, which is important for the paste strength in construction secondary products, and the characteristics of the paste were identified. The factors and levels in this experiment are shown in Table 13, and the compounding tables are shown in Table 14.

First, W / B was 15, 20%, CF was 5, 10, 15, 20, 25, 30%, and the target flow rate of the paste was 150 ± 30 mm. As a method for measuring the flow of the paste, a cylindrical tube having a diameter of 50 × 50 mm was used, and the compressive strength was planned to be measured at ages 3, 7, and 28 days.

The results of the measurement are shown in Figure 13a and 13b paste flow pictures, and in Figures 14a and 14b are shown a picture of the compressive strength by age, Figure 15 and Table 15 shows the compressive strength according to the clinker factor, water binder ratio and age Change.

TABLE 13 Experimental Factors and Levels

factor level W / B (water / cement ratio) 2  15%, 20% Flow One  150 ± 30 mm CF factor 5  5, 10, 15, 20, 25, 30% Metric One  Compressive strength (3, 7, 28 days)

TABLE 14 Formula

division W / B (%) BSC ^* SF ¹⁾ PS ²⁾ GH ³⁾ PL ⁴⁾ GS ⁵⁾ SP ⁶⁾ (%) Remarks  CF0.05 15/20  7.1 2.0 73.9 3.0 7.0 7.0 2.5 / 1.5  CF0.10 14.3 2.0 70.7 3.0 5.0 5.0  CF0.15 21.4 2.0 65.6 3.0 4.0 4.0  CF0.20 28.6 2.0 60.4 3.0 3.0 3.0  CF0.25 35.7 2.0 55.3 3.0 2.0 2.0  CF0.30 42.9 2.0 50.1 3.0 1.0 1.0 * BSC: A blast furnace slag cement 2 types
1) SF: Silica Fume, 2) PS: ordinary portland cement, 3) HG: heavy calcium carbonate,
4) PL: Ca (OH) ₂ , 5) GS: anhydrous gypsum,
6) High performance fluidizing agent (polycarboxylic acid system)

TABLE 15

division Compressive strength Remarks W / B 15% W / B 20% 3 days of age 7 days 28 days old 3 days of age 7 days 28 days old  CF0.05 35.6 50.9 64.2 32.4 49.2 58.8  CF0.1 48.5 74.5 84.5 44.2 56.0 71.8  CF0.15 50.4 81.5 89.3 46.7 63.7 75.6  CF0.2 62.2 86.0 95.1 48.9 67.6 79.2  CF0.25 66.4 87.7 99.0 58.0 68.1 82.1  CF0.3 68.4 95.5 113.1 61.6 77.9 88.3

As shown in FIGS. 13A, 13B, 14A, and 14B and Table 15, the lower the overall W / B and the higher the CF factor, the higher the intensity. At 28 days of age, W / B 20% and CF0.3 were 88.3 MPa, and similar strengths were W / B 15%, CF0.10 and 0.15 at 84.5 and 89.3 MPa, respectively. We believe that B will affect the strength development and low W / B will be important in the production of secondary products.

Experimental Example 3. Production and pilot application of eco-friendly permeable block prototype

Permeable block prototypes were produced using aggregates of waste limestone (low-grade limestone with a CaO purity of 35-45%) in limestone mines. Prototype production was based on the results of the cement clinker factor adjustment test.

(1) Experimental method

1) Prototype Production

Based on the basic experiment adjusting the Clinker Factor (CF), the optimum range of binder was derived. As a result of the experiment, the optimum mixing ratio was considered to be CF 0.15 ~ CF 0.25, considering the strength and fluidity, and the water ratio was 15%. Triaxial flexural strength was measured to investigate the suitability of the actual product as a permeation block.

Aggregate granularity was 3 ~ 5mm, and prototype was manufactured in 250 × 125 × 65mm size. Curing temperature was 28 ℃ to cure for 3, 7, 14, 28, 56 days to measure the bending strength.

2) Pilot application

We tried to determine the suitability of commercialization through field application test of manufactured prototype. The actual production facility was produced using the domestic block production facility of C company, and the pilot application was carried out with a size of about 200 ㎡. The test production process consisted of raw material weighing, dry mixing, dry mortar transfer, mortar mixing, product molding, curing, and product selection.

In addition, for the color test of the product, the red, green, and yellow colorants were used to determine the suitability of mixed use.

(3) Experiment result

1) Prototype Production

Prototypes were prepared from the C.F 0.20 formulation, corresponding to 20% clinker factor, and their strength characteristics were investigated. Curing days were 3, 7, 14, 28, and 56 days, and the average of 10 prototypes was measured after each aging day. Flexural strength (compressive strength) test results are shown in FIG. 17 and Table 16 below. In addition, the photograph of the color permeable block to which the colorant is applied is shown in FIG.

[Table 16] Bending Strength Measurement Results for Each Age

3 days of age 7 days a year 14 days of age 28 days old 56 days One 2.98 3.69 4.58 5.77 6.09 2 2.56 3.69 5.12 5.42 5.84 3 2.36 3.14 4.56 5.64 5.66 4 2.25 3.25 4.64 5.09 5.46 5 2.69 3.89 4.58 5.82 4.66 6 2.15 3.45 4.99 5.56 5.58 7 2.44 3.19 5.01 5.54 5.44 8 2.20 3.98 5.11 6.01 6.10 9 2.56 3.58 5.12 5.40 5.95 10 2.15 3.55 4.82 5.47 4.97 Average 2.43 3.54 4.85 5.57 5.58

As shown in Table 16, the minimum flexural strength of the general permeation block 4N / mm ² is slightly dropped at 7 days of age, but it can be confirmed that it exceeds the standard strength value at 14 days of age, the maximum strength of 5.58 N / mm ² It was shown that the strength increase effect of about 40% was applied to the reference strength value. Therefore, it was judged that it could be utilized as a real permeable product.

Based on the above results, it is expected that the long-term stability of applied blocks due to seasonal change, temperature change, humidity change, etc. will be continuously reviewed and commercialization will be possible through the formulation of block products and adjustment of raw materials.

1 is a photograph showing a cutting specimen of the water permeable block (porous concrete) of the present invention.

Figure 2 shows the compressive strength of the age according to the blast furnace slag substitution rate of the permeable block using 4 ~ 8 mm mine waste-rock, Figure 3 shows the compressive strength of the age according to the blast furnace slag substitution rate of the permeate block using the mine waste-rock 14 ~ 25 mm Figure 4 shows the compressive strength for each age according to the blast furnace slag substitution rate of the permeable block using a 4 to 8 mm fertilizer.

Figure 5 shows the compressive strength for each age according to the aggregate type of the permeable block of blast furnace slag replacement rate 0%, Figure 6 shows the compressive strength for each age according to the aggregate type of the permeable block 25% blast furnace slag replacement rate, Figure 7 The compressive strength for each age according to the aggregate type of the permeable block of blast furnace slag substitution rate 50%, Figure 8 shows the compressive strength for each age according to the aggregate type of the permeable block of blast furnace slag substitution rate 75%.

FIG. 9 shows the correlation between the compressive strength and the unit volume weight of the 14-day water permeable block, and FIG. 10 shows the correlation between the compressive strength and the unit volume weight of the 28-day water permeable block.

FIG. 11 shows the correlation between the compressive strength and the porosity of the 14-day water permeable block, and FIG. 12 shows the correlation between the compressive strength and the porosity of the 28-day water permeable block.

FIG. 13A is a photograph showing a paste flow result according to the clinker factor CF when the water binder content is 15%, and FIG. 13B is a photograph showing a paste flow result according to the clinker factor when the water binder content is 20%.

14a is a photograph showing the results of measuring the compressive strength according to the clinker factor when the water binder content is 15%, Figure 14b is a photograph showing the results of compressive strength according to the clinker factor when the water binder content is 20%.

15 is a graph showing the change in compressive strength according to the clinker factor, water binder ratio and age.

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17 is a graph showing the results of the measurement of the bending strength of each of the permeation block prepared by the combination of clinker factor 0.2.

18 is a photograph of a prototype to which a colorant is applied.

Claims (6)

Low-grade limestone with a CaO purity of 35-45%, natural aggregates or recycled aggregates having a particle size of 3-25 mm, binders and admixtures, water binder ratios of 10-25% and clinker factor of 0.1-0.25 It is made of a paste, characterized in that the continuous porosity after curing is 15 to 25%. The method according to claim 1, The low-grade limestone is a pitcher block, characterized in that included in the range of 85 to 95% by weight of the total weight of the pitcher block. The method according to claim 1, The binder has a blast furnace slag replacement rate for cement is 10 to 30%, characterized in that permeable block. The method according to claim 1, The admixture is a pitcher block, characterized in that the lignin-based supersensitive material. The method according to claim 1, The paste is permeable block, characterized in that the flow is 145 to 155 mm. A process of forming powder by mixing low-grade limestone with a CaO purity of 35 to 45%, a binder and a mixed material, Forming a paste having a clinker factor of 0.1 to 0.25 by adding water to the powder so that a water binder ratio is 10 to 20%, and The process of curing after adding low-grade limestone aggregate having a particle size of 3 to 25 mm to the paste so as to have a porosity of 15 to 25% after mixing Method for producing a water permeable block comprising a.

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