• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.285-292
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• 1998

This study was performed to evaluate the engineering properties of concrete using normal portland cement, natural aggregates and rice-straw ash. The following conclusions were drawn; 1. The unit weight was in the range of $2,250{\sim}2,335kgf/m^3$, the weights of those concrete were decreased 1~5% than that of the normal cement concrete, respectively. 2. The highest strength was achieved by 5% rice-straw ash filled rice-straw ash concrete, it was increased 17% by compressive strength, 30% by tensile strength and 21% by bending strength than that of the normal cement concrete, respectively. 3. The ultrasonic pulse velocity was in the range of 4,059~4,360m/s, which was showed about the same compared to that of the normal cement concrete. The highest ultrasonic pulse velocity was showed by 5% rice-straw ash filled rice-straw ash concrete. 4. The acid-proof was increased with increase of the content of rice-straw ash. The acid-proof was increased 1.15 times by 5% rice straw ash, 1.45 times by 10%, 1.6 times by 15% rice-straw ash filled concrete than that of the normal cement concrete, respectively.

• Korean Journal of Agricultural Science
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• v.26 no.1
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• pp.65-70
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• 1999

This study is performed to evaluate the engineering properties of rice-straw ash concrete using normal portland cement, natural aggregates and rice-straw ash. The following conclusion are drawn; 1. The dynamic modulus of elasticity is in the range of $289{\times}10^3{\sim}345{\times}10^3kgf/cm^2$, which is showed about the same compared to that of the normal cement concrete. The highest dynamic modulus is showed by 5% rice-straw ash filled rice-straw ash concrete 2. The static modulus of elasticity is in the range of $268{\times}10^3{\sim}335{\times}10^3kgf/cm^2$, which is showed about the same compared to that of the normal cement concrete. The dynamic modulus is increased approximately 3~10% than that of the static modulus. 3. The poisson's number of rice-straw ash concrete is less than that of the normal cement concrete. 4. Accordingly, if we use suitable quantity of rice-straw ash as a replacement of cement, it will greatly improve engineering properties of concrete.

• Journal of the Korea Concrete Institute
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• v.16 no.3 s.81
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• pp.311-318
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• 2004

This study was performed to examine engineering properties for planting of porous concrete block containing rice straw ash. Tests for void ratio, compressive and flexural strength, pH by neutralization treatment time and curing method were peformed. As results, the void ratio tends to decrease with increasing rice straw ash content. But, the compressive and flexural strength tends to increase with Increasing rice straw ash content. When the neutralization was treated at the curing age 6 days, the greatest strength was showed. The pH of porous concrete without neutralization treatment in dry and water curing are shown in 10.32 ${\~}$ 10.55 and 9.41${\~}$9.59, respectively. The pH of porous concrete by neutralization treatment in dry and water curing were shown in 9.74${\~}$10.10 and 8.13${\~}$9.32, respectively. The porous concrete block size was 23 ${\times}$ 23 ${\times}$ 4 cm, and species of planting were Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata. At the 6 months after seeding, germination ratio and grown-up length of Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata were shown in 90, 60, $50\%$, and 40${\~}$50, 90${\~}$110, 65${\~}$75 cm, respectively. These porous concrete block containing rice straw ash could be used for planting.

• Magazine of the Korean Society of Agricultural Engineers
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• v.40 no.4
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• pp.103-108
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• 1998

This study examines the physical and mechanical properties of the concrete using rice straw ash. Materials used for this experiment are rice straw ash, normal portland cement, superplasticizer, natural sand and gravel. Test results show that the unit weights of concrete using rice straw ash were decreased 1 ∼ 3% and the highest strengths were achieved by 5% filled rice straw ash concrete, with increase of compressive strength by 19%, tensile strength by 53% and bending strength by 16%, as compared with those of the normal cement concrete. The strength ratio of rice straw ash concrete was higher than that of the normal cement concrete. Also, the durability against sulfuric acid 5% solution was increased with increase of the content of rice straw ash. It was 1.33 times of the normal cement concrete by 10% filled rice straw ash concrete and 1.47 times by 15% filled rice straw ash concrete, respectively Accordingly, rice straw ash concrete will greatly improve the properties of concrete.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.1
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• pp.92-98
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• 2000

This study is performed to evaluate the elastic properties of rice straw ash concrete using reices straw ash, cement, natural sand, gravel, and superplasticizer. The following conclusions are drawn ; The ultrasonic pulse velicity is in the range of 4,084 ~4,336m/s , which has showed about the same compared to that of the normla cement concrete. The highest ultrasonic pulse velocity is showed by 5 % rice straw ash filled rice straw ash concrete. The dynamic and static modulus of elasticity is in the range of 294 $\times$10$^3$ ~347 $\times$ 10$^3$ and 266 $\times$10$^3$~328 $\times$10$^3$kgf/㎤ , respectively. It is showed about the same compared to that of the normal cement concrete. The Poisson's number of rice straw ash concrete is less than that of the normal cement concrete.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.3
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• pp.66-72
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• 1999

The purpose of this experiment is to estimate freezing and thawing resistance of rice straw ash concrete. Test results show that mass, pulse velocity and relative synamic modulus of elasticity are gradually decreased with increase of freezing and thawing cycle. The durability factor(DF) is in the range of 85.48 ∼86.33 in the rice straw ash comcrete with 2.5% , 5% 7.5%, rice straw ash and higher than that of thenormal cement concrete. But, DF of 10% , 12.5%, 15% rice straw ash filled rice straw ash concrete is in the range of 41.26∼65.34 and lower than that of the normal cement concrete.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.161-166
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• 1998

This experiment was on purpose to estimate freezing and thawing resistance concering with developing rice straw ash concrete which were mixed rice straw ash to cement as ratio of cement weight. Freezing and thawing test was done by Method A of KS F 2456. It could estimate change of original mass, pulse velocity and dynamic modulus of elasticity during test. Test results showed that 5% filled rice straw ash concrete had the highest durability factor(DF) as 86 and from 5% to 7.5% filled rice straw ash concrete showed higher DF than normal cement concrete.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.5
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• pp.79-87
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• 2002

This study is performed to examine the physical and mechanical properties of Eco-concrete using rice straw ash for planting. The tests for void ratio, compressive and bending strength with neutralization treatment point, curing condition and coarse aggregate size are performed. The test result shows that the void ratio is decreased with increasing content of rice straw ash. But, the compressive and bending strength are increased with increasing content of rice straw ash. The greatest strength is appeared when neutralization is treated in curing age of 6 days. These Eco-concrete is very useful for planting.

• Magazine of the Korean Society of Agricultural Engineers
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• v.45 no.4
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• pp.107-114
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• 2003

This study was performed to develop the plantable concrete block using rice straw ash and apply for inclined plane. For the planting, plantable concrete block needs infiltration of water and air through void of block. The materials used for plantable concrete block are cement, rice straw ash, and coarse aggregate (5-10, 10-20 mm). Plantable block size is $23\times23\times4$ cm, and species of planting are Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata. At the 6 months after seeding, germination ratio and grown-up length of Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata are shown in 90%, 60%, 50%, and 40~50 cm, 90~120 cm, 60~75 cm, respectively.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.324-329
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• 1999

This study is performed to evaluate an elastic properties of rice straw ash concrete . The following conclusions are drawn ; The ultrasonic pulse velocity is in the range of 4.084 ∼4.336㎧, which has showed abuot the same compared to that of the normal cement concrete. The highest ultrasonic pulse velocity is showed by 5% rice straw ash filled reice straw ash concrete. The dynamic and static modulus of elasticity i sin the range of 294 ${\times}$103 ∼ 347 ${\times}$103 and 266${\times}$ 103 ∼347${\times}$ 103 kgf/$\textrm{cm}^2$ , respectively. It is showed about the same compared to that of the normla cement concrete. The poisson's number of rice straw ash concrete is less than that of the normal cement concrete . The stress-strain curve of concrete which is contained rice straw ash within 10% appear slowly and over 10% appear almost straightly.