• 한국동물학회:학술대회논문집
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• 한국동물학회 1998년도 한국생물과학협회 학술발표대회
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• pp.197.2-197
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• 1998

No Abstract, See Full Text

• 대한기계학회논문집A
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• 제30권8호
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• pp.916-922
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• 2006

In recent years there has been a growing interest for the use of natural fibers in composite applications due to their low cost, environmental friendliness, and good mechanical properties. The purpose of this study is to determine the characteristic of bending strength on bamboo fiber reinforced polymer composites. The parameters of RTM process depend on the weight ratio of bamboo fiber and resin, the number of bamboo ply and amount of hardening agent. Mechanical properties was investigated for each process factor of polymer composites. Test result shows that bending strength was a maximum(approximately 85MPa) value when composite thickness was 6mm and weight ratio of resin was 13%.

• 한국농공학회지
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• 제43권1호
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• pp.116-121
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• 2001

This study is performed to examine the physical and mechanical properties of eco-concrete with polypropylene fiber. Test results show that the strengths are increased with increase of the content of natural gravel, excellent soil compound and polypropylene fiber. The coefficient of permeability is increased with increase of the content of the polypropylene fiber but it is decreased with increase of the content of natural gravel and excellent soil compound. The lowest coefficient of permeability is achieved by eco-concrete which it is 100 times lower than that of the control. The durability factor is increased with increase of the content of natural gravel and excellent soil compound, and decreased with increase of the content of polypropylene fiber.

• Steel and Composite Structures
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• 제10권4호
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• pp.349-360
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• 2010

Three dimensional free vibrations analysis of functionally graded fiber reinforced cylindrical shell is presented, using differential quadrature method (DQM). The cylindrical shell is assumed to have continuous grading of fiber volume fraction in the radial direction. Suitable displacement functions are used to reduce the equilibrium equations to a set of coupled ordinary differential equations with variable coefficients, which can be solved by differential quadrature method to obtain natural frequencies. The main contribution of this work is presenting useful results for continuous grading of fiber reinforcement in the thickness direction of a cylindrical shell and comparison with similar discrete laminate composite ones. Results indicate that significant improvement is found in natural frequency of a functionally graded fiber reinforced cylinder due to the reduction in spatial mismatch of material properties and natural frequency.

• Composites Research
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• 제20권2호
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• pp.32-38
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• 2007

Natural fibers can refer to all types of fibres only produced by nature. Their lengths vary from particles to long strands. Natural fibers are categorized roughly by six types, depending on the types of sources; base, leaf, seed, grasses, fruit and wood. Of these fibers, jute, flax, sisal and ramie are the most commonly used as reinforced materials in preparing polymer composites. In development and improvement of these composites, many studies have been implemented to overcome the drawbacks such as incompatibility, moisture problems and so on. The range of industry sectors of natural fiber-reinforced polymer composites becomes more extensive gradually and many of the companies all over the world are engaged in fabrications or applications. This paper mainly discussed the recent status of the domestic/overseas market and research issues of natural fiber-reinforced polymer composites. We made an exception of wood-polymer composites market which have played a great role because they had been often dealt with.

• 한국자원식물학회지
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• 제2권2호
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• pp.291-297
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• 1989

It was indicated that natural fiber crops Ln Korea have been major crops, such as cotton, flax, ramie and Kenaf. The major varieties andagronomic characterics are summarized as follows. Cotton variety, Mokpo 6 is long fiber length and, is high lint yield, flax variety, Wiera is hiTh amount of dry stem and grains weiTht. On the other hand, kenaf variety, Suweon 2 is high dry fiber weight and fiher ratio.

• Composites Research
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• 제22권4호
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• pp.41-49
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• 2009

천연섬유복합재료는 저비용, 경량, 재생성, 친환경적인 재료로 최근 제조되고 있다. 또한 이들 재료는 생체분해성과 비연마 특성을 갖고 있다. 천연섬유의 친환경적이고 생체분해성으로 인해 천연섬유복합재료는 기존의 섬유를 대체할 잠재적인 대체재로 관심을 받고 있다. 천연섬유의 화학적, 기계적, 물리적 특성은 다양한 섬유의 셀룰로스양에 따라 명확한 특정이 구분되며, 이러한 복합재료의 기계적인 물성치는 기지재와 섬유간의 접착에 의해 주로 영향을 받고 있다. 천연섬유표면의 여러 화학적인 물리적인 개질방법은 섬유와 기지의 접착력 향상에 영향을 주어 결국 복합재료의 기계적인 물성치를 향상시킬 수 있다. 본 논문은 최근 개발되고 있는 천연섬유복합재료의 섬유종류, 고분자기지, 제조기술, 섬유의 처리, 섬유 기지간 계면등에 관한 최근의 연구결과들을 정리하여 소개한 것이다.

• Advances in concrete construction
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• 제13권 2호
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• pp.133-152
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• 2022

Ecological issues such as natural resource reduction and enormous waste disposals are increasingly leading in developing civilization toward sustainable construction. The two primary environmental issues are the depletion of natural resources and the disposal of trash in open landfills. Waste steel fiber (WSF) was investigated for usage as a cement-based concrete (CBC) constituent in this research. Recycling waste fibers both makes cement composites more long and cost-effective, also aids in pollution reduction. The objective of this study is to analyze the impacts of waste fiber on the fresh and mechanical features of concrete using recycled additives. A comparative research on the durability and mechanical qualities of fiber-reinforced concrete (FRC) constructed with natural aggregates was conducted for this aim. The obstacles to successful WSF recycling methods application in the building industry have been investigated, resulting that CBCs with these fibers make an economic and long lasting choice to deal with waste materials. The workability of fiber enhanced concrete was found to be comparable to that of normal concrete. Fibers have a considerable impact on the splitting tensile strength, flexural and compressive strength of recycled concrete. Fiber may enhance the water permeability. When the WSF content is 0.6 kg/m3, the water absorption is nearly half. Fibers would have no effect on its permeability.

• Computers and Concrete
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• 제17권5호
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• pp.597-612
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• 2016

The present work focuses on the use of coconut fiber in self compacting concrete. Self-Compacting Concrete (SCC) is a highly flowable, stable concrete which flows readily into place, filling formwork without any consolidation and without undergoing any significant segregation. Use of fibers in SCC bridge the cracks and enhance the performance of concrete by not allowing cracks to propagate. They contribute to an increased energy absorption compared to plain concrete. Coconut fiber has the highest toughness among all natural fibers. It is known that structures in the seismic prone areas are always under the influence of cyclic loading. To justify the importance of strengthening SCC beams with coir fiber, the present work has been undertaken. A comparison is made between cyclic and static loading of coconut fiber reinforced self compacting concrete (FRSCC) members. Using the test data obtained from the experiment, hysteresis loops were drawn and comparison of envelope curve, energy dissipation, stiffness degradation were made and important conclusions were draw to justify the use of coconut fiber in SCC.

• Composites Research
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• 제36권1호
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• pp.32-36
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• 2023

최근 탄소 중립 등 지속 가능한 발전을 위한 지구환경 문제가 대두되면서 기존 풍력터빈의 소재인 유리섬유 복합재의 폐기 시 처리 방안이 문제가 되고 있다. 이를 해결하기 위해 본 연구에서는 기존의 유리섬유 복합재를 대체할 수 있는 친환경 복합재인 아마섬유 기반 복합재를 활용하여 30kW 풍력터빈 블레이드를 제조하고 적합성을 평가하였다. 먼저 친환경 천연 아마섬유 복합재의 풍력터빈 블레이드 소재로 활용 가능성을 검증하기 위해 기계적 강도 시험을 수행하였으며, 그 결과 선행 아마섬유 복합재 물성 연구 대비 좀 더 우수한 강도가 측정된 것을 확인하였다. 또한 제작된 30kW 급 아마섬유 복합재 블레이드를 활용하여 아마섬유 복합재 블레이드의 정적강도를 측정하는 정적강도 성능평가 시험을 통하여 적합성을 확인하였다.