• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 춘계학술대회 논문집
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• pp.216-219
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• 1995

One of the principal problems encountered in the use of glass fiber reinforced Plastic composites(GFRP) is to establish an active fiber surface to achieve maximum adhesion between resin and fiber surface. In order to develope new process to overcome the disadvantage of chemical agent, we have studied the effect of reactive plasma glass surface treatment on the electrical and mechanical properties of glass fiber reinforced epoxy composites. It is found that the electrical and mechanical characteristics of the composites treated with plasma is improved especially in the dielectric strength by 20% and tensile strength by 15%, whereas the tan $\delta$ is decreased significantly.

• Structural Engineering and Mechanics
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• 제22권3호
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• pp.311-330
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• 2006

Standard compression tests of steel fiber reinforced concrete (SFRC) cylinders are conducted to formulate compressive stress versus compressive strain relationship of SFRC. Axial pullout tests of SFRC specimens are also conducted to explore its tensile stress strain relationship. Cover concrete spalling and reinforcement buckling models developed originally for normal reinforced concrete are modified to extend their application to SFRC. Thus obtained monotonic material models of concrete and reinforcing bars in SFRC members are combined with unloading/reloading loops used in the cyclic models of concrete and reinforcing bars in normal reinforced concrete. The resulting path-dependent cyclic material models are then incorporated in a finite-element based fiber analysis program. The applicability of these models at member level is verified by simulating cyclic lateral loading tests of SFRC columns under constant axial compression. The analysis using the proposed SFRC models yield results that are much closer to the experimental results than the analytical results obtained using the normal reinforced concrete models are.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 2003년도 추계 학술논문발표회 논문집
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• pp.113-117
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• 2003

The reliability of machined fiber reinforced composites (FRC) in high strength applications and the safety in using these components are often critically dependent upon the quality of surface produced by machining since the surface layer may drastically affect the strength and chemical resistance of the material [1,2,3,4]. Current study will discuss the characterization of fiber pull-out in orthogonal cutting of a fiber-matrix composite materials. A sparsely distributed idealized model composite material, namely a glass reinforced polyester (GFRP) was used as workpiece. Analysis method employs a force sensor and the signals from the sensor are processed using AR time series model. The experimental correlation between the fiber pull-out and the AR coefficients is examined first and effects of fiber orientation, cutting parameters and tool geometry on the fiber pull-out are also discussed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.766-771
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• 2000

As using of insulating material of plastic to industrial electric field, thermoset has been gradually substituted for thermoplastic. But changing the material with crystalline has some problem, which is strength or warpage, Especially getting a strength to endure inner pressure is necessary when arc is occurred. So we use the material that is composed of glass fiber to compensate strength. By the way as the reinforced glass-fiber material is used in injection molding, unstableness of dimension is appeared frequently and it is difficult to know warpage pattern. So this paper will be contributed to know warpage pattern of mold product that is upper frame of magnetic contactor caused by glass-fiber orientation with fixed gate-system, when glass-fiber reinforced material with classification of poly-amide is used in injection molding.

• 한국해양공학회지
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• 제30권6호
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• pp.520-525
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• 2016

In this study, a mixture of polypropylene fibers and glass fibers were used to weave polypropylene/glass fiber-reinforced composite panels with characteristics such as highly elongated short fibers, high ductility, anti-fouling, and hydrophobicity as a result of a directional property. Mechanical and environmental tests were carried out with specimens fabricated with this composite panel, and its applicability to shipbuilding and ocean leisure industries was evaluated through a comparison with existing glass fiber-reinforced composite materials. The results of this experiment verified the excellence of the polypropylene/glass-mixed woven fiber-reinforced composite material compared to the existing glass fiber-reinforced composite material. However, the forming process needs to be changed to improve the weak interfacial bonding, and the properties of the composite material itself could be improved through mixed weaving with other fibers after development. Maximizing of the advantages of the polypropylene fibers and overcoming their shortcomings will improve their applicability to the shipbuilding, ocean leisure, and other industries, and increase the value of polypropylene fibers in the composite material market.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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• pp.89-92
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• 1995

For the development of lilght weight cement concrete with high durability, this study used perlite and paper sludge ash by the light weight material, and polypropylene fiber by the reinforcment, and poly-acrylic ester emulsion by the matrix improvement. According to the increasing mixture ratio of fiber and use of polymer, the light weight polypropylene fiber reinforced polymer cement ratio of fiber and use of polymer, the light weight polypropylene fiber reinforced polymer cement concrete were showed high resistance for frost damage.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(II)
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• pp.73-78
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• 2003

As a fundamental study to develop the retaining wall of new type, short-fibers are mixed with soils and a series of compaction tests and triaxial compression tests for short-fiber reinforced soils are performed. From the results of compaction tests, optimum moisture content is increased and maximum dry unit weight is decreased with fiber mixing ratio. When 60mm fibrillated fiber of 0.2$\%$ mixing ratio is added to SM soil, strength increment of short-fiber reinforced soil is above 1.2 times compared to soil only. Strength increment shows maximum value for composite reinforced soil, namely, soil+short-fiber+planar reinforcement. But in case of mixing with ML soil and short-fiber, the strength of short-fiber reinforced soil is nearly the same as soil only. Internal angle of short-fiber reinforced soil is increased about $2\~3$ degrees and cohesion is also increased above 10kPa compared to soil only. Therefore, it is judged that short-fiber is a good material to strengthen the soil.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2001년도 춘계학술대회
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• pp.258-258
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• 2001

Fiber-reinforced materials have highly favorable mechanical properties. and their strength-to-weight ratios are superior to those of most alloys. When compared to metals they offer many other advantages as well. including non-corrosiveness. translucency. good bonding properties. and ease ofrepair. Fiber-reinforced materials can be categorized to pre-impregnated. impregnation required. dental laboratory products. chairside products and prefabricated posts. so it is not suprising that fiber-reinforced composites have potential for use in many applications in dentistry. Fiber-reinforced materials can be utilized in frameworks for crowns. anterior or posterior fixed prostheses. chairs ide tooth replacements. periodontal splints. customized posts. prefabricated posts. orthodontic retention. denture reinforcements and in implants dentistry. To realize the full potential of using fiber-reinforced composite restorations. it is essential that the clinician and laboratory technician understand concepts of tooth preparation and framework design. Also practitioner may appreciate the background information and other details about the materials themselves so that identify the rationale for their use in various clinical situations. select well-suited materials. and carry out related procedures. Understanding the material properties and take many attentions. fiber-reinforced materials will give more esthetic. more easy. more strong and more reliable restorations.ations.

• 한국농공학회논문집
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• 제58권1호
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• pp.53-59
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• 2016

This study was conducted by the slump test and the consistency test of the fiber mixed soil which is soil reinforced with fiber as a reinforced material to investigate and estimate the difficulty degree of work and the proper water content. So I would like to present the fundamental data that establishes the work standard of the fiber mixed soil. In conclusion, in this study the slump value of the fiber mixed soil increases over-all according to the increase of the water content although it has a little difference of the increase range and it is smaller than one of the soil. It is estimated that the aggregating and throwing work of the fiber mixed soil would be fine when it has the about 25 % water content and the wall and floor plastering work is the about 30 % ~ 35 % and the flowing and pouring work is the about 40 % water content as well as the mold compacting work is the about 20 %. There is no decreasing of the workability when the soil is reinforced by the fiber because the workability characteristics of the fiber mixed soil is similar to the one of the soil. Therefore, It is estimated that using the fiber as a reinforced material of soil would be appropriate for the construction.

• 한국공간구조학회논문집
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• 제7권3호
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• pp.141-151
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• 2007

The appearance of many Glass Fiber Reinforced Plastic (GFRP) constructions look like ordinary steel construction, because GFRP has been imitated by the same way with the traditional steel's cross section as well as connection system. In terms of detachable connection, there was not enough appropriate option of GFRP connection, such as a traditional bolt connection for steel and wood structures. Most of all, from material characteristic of GFRP related to the deficient ductility, the shearstress principle of GFRP s not proper for the material property, which causes ineffective and not economic application of material. With this research problem, the innovative and detachable onnection system, which is more considered with appropriate material characteristic for FRP, is developed. Not only short time but also long time research with various connection variations is carried out.