• 한국농공학회논문집
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• 제56권5호
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• pp.45-54
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• 2014

This study was performed to evaluate compressive strength, flexural strength, static modulus of elasticity, stress-strain ratio and durability of abrasion on EVA concrete reinforced steel fiber (SF) in order to use hydraulic structures, underground utilities, offshore structures and structures being applied soil contaminated area. It is used ordinary portland cement, crushed coarse aggregate, nature fine aggregate, EVA redispersible polymer powder, superplasticizer and deforming agent to find optimum mix design of EVA concrete reinforced steel fiber. EVA concrete reinforced SF was effected on the improvement of mechanical properties and durability of abrasion.

• 한국지반공학회논문집
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• 제31권6호
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• pp.15-25
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• 2015

본 연구는 연약지반의 강도증진을 목적으로 친환경 헤어섬유를 혼입한 점토흙의 강도 특성을 파악하였다. 본 연구에서는 헤어섬유의 길이 및 혼입율, 시멘트의 첨가량, 양생기간을 변화시키며 헤어섬유 혼입 점토흙의 압축강도 및 인장강도를 조사하였으며, 또한 응력-변형율 특성을 조사하였다. 시험결과, 헤어섬유 혼입점토는 압축 및 인장 모두에서 강도증진을 보였으며, 특히 인장강도에서 보다 큰 효과가 있는 것으로 나타났다. 뿐만 아니라, 헤어섬유 혼입점토가 파괴시까지 더 큰 변위를 허용하는 것으로 나타났다. 이와같은 결과를 토대로 향후 점토지반 강도증진을 위해 친환경 재료인 헤어섬유를 실무적으로 활용해도 될 것으로 판단된다.

• 한국농공학회논문집
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• 제46권6호
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• pp.13-19
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• 2004

This study was performed to evaluate permeable properties of eco-concrete using soil, natural coarse aggregate, soil compound and polypropylene fiber. The fIexural strength, ultrasonic pulse velocity and dynamic modulus of elasticity were increased with increasing the content of coarse aggregate, soil compound and polypropylene fiber. The flexural strength, ultrasonic pulse velocity and dynamic modulus of elasticity were 259 MPa, 3,527 m/s and 275 ${\times}$ 102 MPa at the curing age of 28 days, respectively. The coefficient of permeability was decreased with increasing the content of coarse aggregate and soil compound, but it was increased with increasing the content of polypropylene fiber. Accordingly, this concrete can be used for farm road.

• 한국농공학회논문집
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• 제46권1호
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• pp.35-40
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• 2004

This study is performed to examine the physical and mechanical properties of eco-concrete using soil, natural coarse aggregate, excellent soil compound and polypropylene fiber. The test result shows that mass loss ratio is decreased with increasing the content of coarse aggregate and excellent soil compound. The compressive and flexural strengths are increased with increasing the content of coarse aggregate, excellent soil compound and polypropylene fiber. The coefficient of permeability is decreased with increasing the content of coarse aggregate and excellent soil compound, but it is increased in 0.2% polypropylene fiber content. The lowest coefficient of permeability is showed in $5.066\times 10^{-9}$cm/s. These eco-concrete can be used for farm road.

• 한국지반신소재학회논문집
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• 제3권1호
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• pp.43-52
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• 2004

단섬유를 혼합한 토사를 뒤채움재료로 사용한 보강토옹벽의 재하하중 단계 및 보강재 포설단수 별 거동특성을 평가하기 위하여 일련의 축소모형실험을 수행하였다. 높이 $100cm{\times}$길이 $140cm{\times}$폭 100cm 인 모형토조를 사용하여 1m 높이의 모형 보강토옹벽을 축조하였다. 본 모형실험에서 보강재로는 최대인장강도 0.79t/m인 지오네트와 최대인장강도 2.26t/m인 지오그리드를 사용하였으며, 화강풍화토에 폴리프로필렌 단섬유를 혼합한 토사를 뒤채움재로 사용하였다. 모형 보강토옹벽 축조후 5단계의 등분포하중($0.5kg/cm^2$, $1.0kg/cm^2$, $1.5kg/cm^2$, $2.0kg/cm^2$, $2.5kg/cm^2$)을 재하하면서 보강재의 인장변형 보강토옹벽 수평변위를 측정하여 하중재하시 모형 보강토옹벽의 거동특성을 평가하였다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.239-244
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• 1999

In this study , the variation of dry density and unconfined compressive strength were investigated, calcium carbonate, quicklime, portland cement, 19mm monofilaments and fibrilllated fibers were used as reinforcement materials. And calcium chloride was added to cement and calcium carbonate reinforced soil mixture in order to accelerate setting and hardening speed. It appears that dry density is highest in calcium carbonate reinforced soil mixture with 9% of mixing rae. According to increasing the amount of fibers, in soil mixture , the dry density decreased. The more the amount of monofilament fibers is the higher the compressive strength. But the compressive strength is decreased in fibrrillated fiber added soil mixture with more than 1.0% of mixing rate.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.321-324
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• 2002

To analyze the settlement characteristics of short-fiber reinforced soil(SFRS) under dynamic loading, a series of tests with loading condition of 5 Hz frequency and 500,000 cycles were performed. The materials used for tests are a soil of SM type and short-fibers with polypropylene and monofilament or fibrillated type. From the tests, average plastic settlement of SFRS at PPF38(0.3%), PPF38(0.5%), PPM60(0.2%) is low. Elastic settlement of SFRS is low at PPM60(0.2%) and is high at PPF60(0.5% ).

• 한국지반공학회논문집
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• 제16권6호
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• pp.87-95
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• 2000

A series of consolidated undrained triaxial compression testes were performed to increase field applications of soil admixtures mixed with short fiber. Kaolin clay and three types of fiber were selected and auto cutter was used to obtain reliable length of fibers. Remolded soil specimens were tested for obtaining the basic data to be applied to the reinforcement of soft clay, embankment or barrier and clay liner of wastes landfill etc. Conversion equations from weight to volume of clay mixed with short fiber are introduced and relationships between fiber content and fiber concentration are derived. It is found that reinforcing effect by aspect ratio and mixing ratio of short fiber decreases as confining pressure increases. The best efficient reinforcing effect is given at the aspect ratio of 80~120 and the fiber content of 1.2%~2.4% and the fiber diameter of 0.27mm.

• Geomechanics and Engineering
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• 제22권3호
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• pp.227-236
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• 2020

Expansive soils are renowned for their swelling-shrinkage property and these volumetric changes resultantly cause huge damage to civil infrastructures. Likewise, subgrades consisting of expansive soils instigate serviceability failures in pavements across various regions of Pakistan and worldwide. This study presents the use of polypropylene fibers to improve the engineering properties of a local swelling soil. The moisture-density relationship, unconfined compressive strength (UCS) and elastic modulus (E₅₀), California bearing ratio (CBR) and one-dimensional consolidation behavior of the soil treated with 0, 0.2, 0.4, 0.6 and 0.8% fibers have been investigated in this study. It is found that the maximum dry density of reinforced soil slightly decreased by 2.8% due to replacement of heavier soil particles by light-weight fibers and the optimum moisture content remained almost unaffected due to non-absorbent nature of the fibers. A significant improvement has been observed in UCS (an increase of 279%), E₅₀ (an increase of 113.6%) and CBR value (an increase of 94.4% under unsoaked and an increase of 55.6% under soaked conditions) of the soil reinforced with 0.4% fibers, thereby providing a better quality subgrade for the construction of pavements on such soils. Free swell and swell pressure of the soil also significantly reduced (94.4% and 87.9%, respectively) with the addition of 0.8% fibers and eventually converting the medium swelling soil to a low swelling class. Similarly, the compression and rebound indices also reduced by 69.9% and 88%, respectively with fiber inclusion of 0.8%. From the experimental evaluations, it emerges that polypropylene fiber has great potential as a low cost and sustainable stabilizing material for widespread swelling soils.

• KCI Concrete Journal
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• 제14권4호
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• pp.161-169
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• 2002

The mechanical properties of fiber reinforced porous concrete for use as a planting material were investigated in this study. Changes in physical and mechanical properties, subsequent to the addition of carbon fiber and silica fume, were studied. The effects of recycled aggregate were also evaluated. The applicability as planting work concrete material was also assessed. The results showed that there were no remarkable changes in the void and strength characteristics following the increase in proportion of recycled aggregate. Also, the mixture with 10% silica fume was found to be the most effective for strength enforcement. The highest flexural strength was obtained when the carbon fiber was added with $3\%$. It was also noticed that PAN-derived carbon fiber was superior to Pitch-derived ones in view of strength. The evaluation of its usage for vegetation showed that the growth of plants was directly affected by the existence of covering soil, in case of having the similar size of aggregate and void.