• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.132-137
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• 2012

To enhance the CAE accuracy, the definition of material behavior is one of key influence on the result. In case of plastic material with fiber reinforcement, the anisotropic material behavior should be taken into account to increase of CAE accuracy. BASF has developed an innovative CAE tool, ULTRASIM$^R$, which is capable of generating material models of thermoplastic materials for structural simulation. ULTRASIM$^R$, not only the glass fiber orientation effect, but also the weld line effect, tensile-compression anisotropy, strain rate effect are combined in a non-linear material law, which will be evaluated in a unique failure criterion, thus resulting in an highly accurate CAE approach.

• Journal of the Korean Geosynthetics Society
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• v.4 no.2
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• pp.3-9
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• 2005

Natural fiber mat made with compressed coconut mat and jute filter is in the spotlight recently as an alternative material for sand mat, which is getting expensive in Korea. Tensile strength and permeability tests for the natural fiber mat were carried out to evaluate for its practical use in this study. Despite of very low tensile strength of coconut mat, that of jute filter was satisfied with conventional criteria of geotextile suggested by Christopher and Holtz(1985). Besides, permeability of fiber mat under high compressive pressure was greater than that of conventional sand material used as sand mat. It was found that the fiber mat has a great potential in substituting the conventional sand material.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.4
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• pp.59-66
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• 2011

This study was carried out to develop the automation bark peeling process of paper mulberry for making Hanji. Nowadays, almost raw material has been imported from south-east asia for making Hanji. Raw material dependence is very high for Hanji-making by low productivity in korea. This study is focused on the resolution for problem of bark peeling automation. Water and sand jet of compressed air was possible bark peeling for black bast fiber. The effect of removing black bast fiber increased the longer the steaming time. Also using drum of bark peeling showed that results under temperature $80^{\circ}C$ and Rpm 50/min were best bark peeling and separating bast fiber from stem. The contents of holocellulose, lignin, ethanol-benzene extractives, and ash were 91.63~95.55%, 1.4~2.0%, 1.12~1.65%, and 1.4~4.3%, respectively. Chemical characteristics are similar between imported raw-material with drum bark.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.450-455
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• 1997

In recent years the research and development about the new material proceeds rapidly and actively in building industry. We are concerned with high-strength concrete as a new material. As the building structure becomes bigger, higher and more specialized, so does the demand of material and member with high strength for building expands greatly. In the future, we will quite need to research repair and rehabilitation to make high strength concrete structural building for our safe. So, I did an study on carbon fiber sheet rehabilitation(CFSR) of reinforced high strength concrete beams. The carbon fiber reinforced plastic(CFRP) bonding method is widely used for reinforcing the existing concrete structure among the various methods. The test results indicate that CFS is very effective for strengthening the damaged beams and controlling deflections of the repaired beams. When carbon fiber sheet rehabilitation of reinforced high strength concrete beams happened diagonal crack, the increase in the number of CFS layer didn't effect the increase in strength of beams. Also, by changing the CFS stick position gave diversified ultimate load in CFSR beams.

• Proceedings of the Korean Fiber Society Conference
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• 2007.11a
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• pp.473-474
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• 2007

• Journal of The Korean Society of Agricultural Engineers
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• v.58 no.1
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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.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.2
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• pp.204-211
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• 2020

Poly-Lactic Acid(PLA) fiber is an eco-friendly material and is biodegradable, so it can be utilized for manufacturing porous construction materia ls with interna l pore connection. In this study, domestic PLA fiber products(0.5mm india meter, 1.0mm in length, 10mm in length) were tested for melting at high temperatures and high alkality, and they were incorporated with FA-based geopolymer. Compressive strength was obtained through high temperature curing and alkali activator, however the complete melting of the PLA fiber was not ensured. The previous study handling PLA fiber with 0.003mm in diameter was completely dissolved, but 0.5mm and 1.0mm in diameter showed 42.5% and 33.3% of dissolution ratio, respectively. In addition, the increasing fiber volume led floating fibers during curing, which had a negative effect on its workability and solubility. Although the properties of PLA fiber may vary depending on the raw materials and production conditions, PLA fiber with 0.1mm or less diameter is recommended for porous construction material.

• KCI Concrete Journal
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• v.14 no.4
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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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.819-822
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• 2001

Fiber waviness is one of manufacturing defects encountered frequently in thick composite structures. It affects significantly on the behavior as well as strength of thick composites. Thick composites with fiber waviness have two kinds of nonliearity. One is material nonlinearity, and the other is geometrical nonliearity due to fiber waviness. There are only a few studies that have considered both material and geometrical nonlinearities. In this paper, a FEA model was proposed to predict nonlinear behavior and strength of thick composites with fiber waviness.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.651-658
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• 2002

A series of experimental study are performed to evaluate the shear strength and friction properties of fiber-mixed soil as backfill material in reinforced earth wall. In order to evaluate the properties of shear strength the big-size direct shear tests are carried out and on the friction properties, the shear friction tests and the pull-out tests are performed. In the results, when the mixed ratio of the net type fiber is 0.2%, the reinforcement effect was better than the others. Also the reinforcement effect of the net type fiber was larger than that of the line type fiber.