• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.35-39
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• 1999

Results of two-part wedge analysis and centrifuge test executed by Zornberg et al. were compared for geotextile-reinforced slope stability. For two-part wedge analysis results of two cases, a frictional case considering internal friction of soil as interwedge friction and a nonfrictional case not considering, were also compared and evaluated. The analysis was based on limit equilibrium and two-part wedge was divided into slices as many as the number of geotextiles to obtain a maximum tension distribution mobilized in reinforcements. A significant observation was that the distribution was a triangular shape with maximum tension of geotextile at a transit point of interwedge. The number of geotextiles and failure surface of frictional case were reasonable and more comparable to results of the centrifuge tests than those of nonfrictional case. Therefore it can be said that two-part wedge analysis is recommendable for design analysis of reinforced slopes if an interwedge angle is regarded to be an angle of internal friction in soil.

• Geotechnical Engineering
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• v.3 no.4
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• pp.55-70
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• 1987

The use of reinforced earth is not new. But available information on basic proper.ties like strength and deformation behavior of reinforced earth materials is not adequate. Therefore, tile purpose of this present investigation is first to research the frictional characteristics of the reinforcement and standard rand using a shear testing appratus. The second purpose of this articles are to report the results of comparison test on the strength and stress-strain behavior of a dry sand einforced with aluminium fcils and geotextiles under different confining pressures. Finally, the paper explores the possibility of geotextile reinforced earth masonry walls. It was observed that the stress-strain response of sand ai.e considerably improved by the introduction of geotextiles. The results of tests are used in developing the geotextile reinforced earth masonry walls. It is hoped that this paper will be helpful in providing the basic data for the rational design and construction methods of reinforced earth structures.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.362-363
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• 2003

직포매트(Woven Ggeotextiles)는 연약지반 보강, 도로포장 등에 주로 사용되고 있지만, 간척지 지반 공사 및 해안지역 LNG 저장고 공사 둥에도 보강용 및 오탁방지막의 막체로도 이용되고 있다 한편, 장기간 시공의 경우 현장에서 대부분 커버를 씌운 상태로 야적, 보관되거나 일차 포설된 채로 한달 이상 경과하는 경우도 발생하게 되어 일광이나 자외선 등에 노출된 채로 있기 때문에 설계 인장강도의 저하를 초래하거나 열수축에 의한 치수변형이 발생하기도 한다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.366-367
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• 2003

토목합성재료의 내후성은 사용되는 원료 물질, 기후조건, 하중조건, 노출 기간 등에 따라 상이한 결과를 나타내며, 이러한 영향인자에 대한 많은 연구가 국내외적으로 이루어졌으나 이는 각 적용지역의 환경조건을 고려하여 실시된 경우로 지역적인 조건과 기후 차이로 국내 여건에 적합한 데이터라 할 수 없다. 본 연구에서는 임시구조물로 적용된 분리형 보강토 옹벽의 전면체를 형성하는 부직포 지오텍 스타일에 대해 현장 적용 노출시험을 실시하였으며 약 1년 간의 지속적인 계측을 통해 실제 국내 현장에서 나타나는 부직포 지오텍스타일의 내후성 거동에 대해서 평가하였다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2003.10a
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• pp.106-106
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• 2003

6 woven geotextiles for reinforcement were used to examine the effects of weatherability and reduction factor on the tensile properties. Decrease of tensile strength as the tool of these evaluations of woven geotextile was examined.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.420-423
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• 2001

토목합성재료(Geosynthetics) 중 직포매트는 i) 분리, ii) 보강/보호 등의 기능을 가지고 있으며 연약지반 보강, 도로포장, 간척지 지반 공사 및 해안지역 LNG 저장고 공사, 폐기물 매립지의 사면 및 저면 보호재 등 기초 보강재료로 널리 이용되고 있다. 그러나 현재 토목건설공사에 사용되고 있는 직포매트용 봉합사는 타이어 코드 제조용 폴리에스테르 고강력사이며, 봉합할 경우 원통형 관입에 의한 인장신도가 커지게 되어 변형에 의한 파괴가 쉽게발생한다. (중략)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.163-172
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• 1990

The filter criteria of geotextiles to prevent excessive loss of fine particles in cohesion-less soils are largely depend on the flow conditions of water in soil/geotextile systems. In the soil/geotextile system under uni-directional flow conditions, it is adequate to retain only the coarse soil fraction because a 'self-induced' soil filter layer may form in cohesionless soil adjacent to the geotextile. In alternating flow conditions, however, a complete soil filter layer within the soil will not form and thus the geotextile pores must be small enough to retain finer particles of the soil to be protected. Based on these concepts, theoretical filtration criteria of geotextiles are developed considering the flow conditions of water. To test the validity of these criteria, laboratory testing was carried out. This indicated that large losses of fine particles would result, especially at high hydraulic gradients, short periods and low vertical loads. The revised filtration criteria are proposed evaluating effect of various design factors.

• Journal of the Korean Geosynthetics Society
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• v.9 no.1
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• pp.21-30
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• 2010

To understand the deformation behavior of nonwoven geotextiles(NWGT) reinforced soil wall, analyses of load-elongation properties, soil-reinforcement interface friction, laboratory model tests, and field cases throughout literature reviews are being studied in this paper. According to the analyses results, the stiffness and tensile strength of NWGT is increased in proportion to confinement pressures, and the interface shear strength at soil-NWGT appeared to be stronger than soil-geogrid interface. The deformation at the beginning of loading on NWGT reinforced soil wall is larger than geogrid reinforced soil wall, but the wall deformation with NWGT is smaller than the wall of geogrid after passing some loading point in laboratory model tests. Case analysis results have shown that the facing of NWGT reinforced soil wall should be rigid enough to be used as a permanent wall, and NWGT and in-situ poor soil can be used for reinforcement and backfill respectively if the wall is constructed as pre-reinforced soil body and with post-facing that has a full-height rigid concrete.

• Advanced Composite Materials
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• v.17 no.3
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• pp.235-246
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• 2008

This paper is concerned with geotextiles bonded chemically with geogrid to form a geocomposite. Geotextiles, thermally bonded and non-woven, play an important role as a separator. Also, this study investigates the resistance to the application environment of geotextile composites. Here, numerous tests have been performed and it was revealed from experimental results that thermally bonded geotextile in geosynthetic composites showed superior characteristics to that manufactured from needle punched non-woven method in terms of tensile strength, tensile strain and high separation performance. It was noted from experiments that the geotextile prepared for separation purpose and manufactured in a thermal bonding method showed relatively low permittivity so that it could be used as a smooth separator. In addition, PVA geotextile/HDPE geomembrane composites were designed and manufactured to investigate the waste landfill related properties. Numerous experiments have been performed and experimental results were summarized to evaluate practical applicability of PVA geotextile/HDPE geomembrane composites. Among the properties of proposed geomembrane composites, evaluation has been focused on the investigation of mechanical properties, AOS (apparent opening size), permittivity and ultraviolet stability.

• Journal of the Korean Geotechnical Society
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• v.23 no.2
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• pp.19-27
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• 2007

Dry and wet test methods established by Korean industrial standards to estimate opening size of 3 types of geotextile which are widely used for filter of plastic drain board in Korea are performed to evaluate characteristics of the test methods and to compare the test results. Judging from test results, dry method is a relatively poor test, having lots of problems causing many errors but a simple-quick test. Wet method is a very specific test avoiding many of the problems of dry method such as electrostatic charges, trapping in the geotextiles and so on. However, one of wet test methods, KS K ISO 12956, takes long time to complete a test and is too strict to handle loss of granular material. Generally, opening size of a geotextile by wet test method is smaller than that of dry test method. Especially, opening size by KS F 2126 which is called hydrodynamic method but at present is not used anymore is similar to or smaller than that by KS K ISO 12956 method.