• Title/Summary/Keyword: tensile fabric structure

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Study on the Development of Reinforced Earth Retaining Wall (보강옹벽개발연구)

  • 유용환
    • Geotechnical Engineering
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    • v.2 no.3
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    • pp.51-66
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    • 1986
  • The design of fabric reinforced retaining wall structure was discussed in this article. It was confirmed that the reinforced retaining earth wall which was designed by new theoretical formulae developed this time was stable structurally and economically. The plastic fabric filter which was placed in layers behind the facing element reduced the lateral earth pressure on the wall elements in comparison with a conventional retaining earth walls. The reinforcing characteristics of earth wall was governed by the spacing of fabric layers, effective length of fabrics, particle distribution and compaction, and thus it is essential that, in the construction field, the reinforcing strips should be selected in order to develop the maximum friction forces bet.eon soil and fabric filters. The maximum tensile stress developed from the reinforcing strips was appeared at a little far distance from the back of skin element and it was not well agreed with the Rankine's theory but distributed well as a symmetrical shape against the point of the maximum tensile stress. The total length of the different layers should be sufficient so that the tension in the fabric strip could be transferred to the backfill material. Also the total stability of reinforced earth wall should be checked with respect to a failure surface which extended blond the different lathers.

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Changes in Waterproofness and Breathability after Repeated Laundering and Durability of Electrospun Nanofiber Web Laminates (전기방사한 나노섬유 웹 라미네이트 소재의 반복 세탁에 따른 투습방수 성능 변화 및 내구성)

  • Lee, Kyung;Yoon, Bo-Ram;Lee, Seung-Sin
    • Fashion & Textile Research Journal
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    • v.14 no.1
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    • pp.122-129
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    • 2012
  • To develop a waterproof breathable material, we fabricated three kinds of nanofiber web laminates using a massproduced electrospun nanofiber web with different substrates and layer structures. The waterproofness and breathability of nanofiber web laminates were evaluated after repeated launderings and compared with those of conventional waterproof breathable fabrics currently in use, including densely woven fabric, microporous membrane laminated fabric, and coated fabric. The durability of nanofiber web laminates, including adhesion strength, abrasion resistance, tensile strength, and tearing strength, was also assessed and compared with those of conventional waterproof breathable fabrics. The water vapor transmission of nanofiber web laminates increased slightly after repeated launderings, whereas the air permeability somewhat decreased after launderings but still maintained an acceptable level of air permeability. Laundering reduced the resistance to water penetration of nanofiber web laminates, which implies that laminating techniques or substrate materials that could support waterproofness of the laminated structure should be explored. The adhesion strength, abrasion resistance, tensile strength, and tearing strength of nanofiber web laminates were in a range comparable to conventional waterproof breathable materials.

Present State of Membrane Structures in Japan

  • Oda, Kenshi
    • Journal of Korean Association for Spatial Structures
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    • v.2 no.2 s.4
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    • pp.11-15
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    • 2002
  • Formerly, it was called a tent and now, it is called membrane structure. If saying a tent, it imagines the tent of Bedouin, Mongolia and North American Indian. It became clear from the excavated wall painting that have been covered with the retractable roof of the canvas on the auditorium at the amphitheater in Pompeii and became a topic. These tents were made of the animal skins or fabric woven with the flax plants, and these tents are still used. However, if saying membrane material at present, it says the one to have applied a coating resin to the textile. Because the base fabric of membrane material is a woven fabric, the relation between the stress and the strain is different to the direction of the weaving thread. Moreover, the tensile force must always occur in the membrane surface. From these reasons, because the membrane structure corresponds to the particular building material and the construction method about the Building Standard Law, it must be examined specially that the membrane structural building have the same or any more safety as the provisions which was set to the Building Standard Law. Therefore, the technical standards about the membrane structural building became indispensable. In the paper, the kinds of the membrane materials, which are used for the membrane structural buildings, and technical standards process of the creating for the membrane structure buildings are introduced. Lastly, some of the soccer stadiums for 2002 FIFA World Cup KOREA/JAPAN which be covered with the roof of the membrane structures are presented.

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The Evaluation of Interlaminar Fracture Toughness and AE Characteristics in a Plain Woven CFRP Composite with DCB Specimen (DCB 시험편의 평직 CFRP 복합재 층간파괴인성 및 AE 특성 평가)

  • Yun Yu-Seong;Kwon Oh-Heon
    • Journal of the Korean Society of Safety
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    • v.20 no.1 s.69
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    • pp.49-54
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    • 2005
  • Recently, many kinds of advanced composite materials have been used in various industry fields. Among them, fabric CFRP composites are being used as primary structural components in many applications because of their superior properties. However, the complexity of the fabric structure makes understanding of their failure behavior very difficult. The mechanical strength and crack propagation of plain woven carbon fiber fabric laminate composites are examined by acoustic emission(AE) method. AE signals are acquired during the tensile test and fracture tests. Thus, the relationship between AE signal and mechanical behavior curves and crack extension length are shown. Also the interlaminar fracture toughness in terms of AE characteristics are discussed in viewpoint of crack propagation behavior.

Study of the Relation between Quality and Image of the WholeGarment Knit Structured Patterns for High Sensible knit Design (1) - On mechanical property to armhole connecting part (Machi) - (고감성 니트디자인을 위한 무봉제 니트 조직패턴의 성능과 이미지간의 연구 (1) - 암홀 접속부(마치)의 역학적 특성을 중심으로 -)

  • Lee, Yoo-Jin;Choi, Won-Jung
    • Journal of Fashion Business
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    • v.16 no.1
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    • pp.52-68
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    • 2012
  • To achieve the aim of this study, 9 different types of samples were made to examine mechanical property according to structured pattern and type of Machi of pullover armhole of WholeGarment(seamless knitwear). With respect to samples, from which comparisons are made and anaylzed among basic characteristics of material, tensile strength & elongation and residual elongation due to repeated extension of armhole connecting part, the following conclusions could be obtained. It's revealed that the tensile strength of Machi part as being armhole connecting part of samples is more affected by Machi type than pattern structure. Of Machi types, it showed stronger tensile strength in the order of Normal(Normal Machi)< Machi_B(unilateral Machi)

Analysis of CAD Design and Physical Properties of Double-raschel Spacer Fabric (더블라셀 소재의 CAD에 의한 표현과 물성연구)

  • Choi, Kyoungme;Kim, Jongjun
    • Journal of Fashion Business
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    • v.23 no.1
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    • pp.37-48
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    • 2019
  • WKSF (Warp-knitted spacer fabrics) knitted using a double Raschel machine is the three-dimensional knit that has vertically connected separate layers in loop structures. Because of its unique structure, the fabric is light, compressible and breathable. Owing to the high production speed, the use of the fabric is increasing in various areas. The purpose of this study is to establish the design process in the utilization of WKSF program and analyze the difference between WKSF and Neoprene as garment materials.. The study on the design related to WKSF has rarely been carried out because of the complexity of WKSF structure and the difficulties encountered in analyzing the structure and thread. Therefore, checking beforehand the simulation results similar to a final knit using the CAD program for WKSF can only enhance the efficiency of the design for the light knits. The conclusion drawn after designing the light knits using the CAD program and analyzing the pros and cons of WKSF through the various property evaluation techniques is as follows. The tension characteristic analysis results indicated that Neoprene specimen has the elastic transformation and resilience, thus behaving like an elastic product such as rubber. By contrast, in the event that clothing and fashion accessories are designed with WKSF, these products are kept in a boxy style fit so that the fabric can be applied flexibly to a curvy body line. In addition, WKSF is good in forming noticeably around a curvy body, because its resistance shear deformation is lower than that of Neoprene.

Wearing Performance and Comfort Property of PTT/Wool/Modal Air Vortex Yarn Knitted Fabrics (PTT/Wool/Modal Air vortex사 편성물의 의류 착용성능과 쾌적물성)

  • Kim, Hyunah
    • Journal of the Korean Society of Clothing and Textiles
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    • v.40 no.2
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    • pp.305-314
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    • 2016
  • This paper investigated the applicable possibility of PTT and wool staple fibers to the air vortex system as high quality yarns for a high emotional and comfort garment. It was found that the tactile hand of vortex yarn knitted fabrics was harsher than ring and compact yarns knitted fabrics. It was observed that formability and sewability of air vortex yarn knitted fabrics seemed worse than ring and compact yarns due to low tensile and compressional resilience and high bending and shear hysteresis of air vortex yarn knitted fabrics. It revealed that wicking and drying rates of air vortex yarn knitted fabric were better than ring and compact yarns; in addition, the heat keepability of vortex yarn knitted fabric was higher than ring and compact yarns due to low thermal conductivity and max heat flow rate ($Q_{max}$). Any difference of thermal shrinkage between air vortex and ring yarn knitted fabrics was not shown, but pilling characteristic of air vortex yarn knitted fabric was superior. However, it was shown that wicking, drying, thermal property and pilling characteristics of air vortex yarn knitted fabric were superior due to air vortex yarn structure with parallel fibers in the core part and periodical and fasciated twists in the sheath part of the yarns.

Fine Structure and Physical Properties of Cotton Fibers and their Fabrics Treated with Liquid Ammonia, NaOH, and NaOH/Liquid Ammonia (액체암모니아, 수산화나트륨, 수산화나트륨/액체암모니아 처리한 면의 미세구조 및 물성)

  • 배소영;이문철;김홍성;이영희;김경환
    • Textile Coloration and Finishing
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    • v.6 no.2
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    • pp.47-54
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    • 1994
  • Cotton fiber, NaOH-mercerized cotton fiber, cotton fabric, and NaOH-mercerized cotton fabric have been treated by liquid ammonia at -33.4$^{\circ}C$. The fine structures, bending properties, tensile strengthes, shrinkages for laundering, and wrinkle recoveries were studied. The treatment of cottons with liquid ammonia brought about the transition of crystal lattice ; transforming cellulose I crystal of original cotton to cellulose I and III crystal, and cellulose II crystal of mercerized cotton to cellulose II and III crystals. The degree of crystallinities were decreased in the order of liquid ammonia>NaOH/liquid ammonia>NaOH-treated cotton. However moisture regain and water absorbency for liquid ammonia-treated cotton were lower than that of NaOH-treated cotton because of a difference in swelling actions of the agents. It seems caused by intermicrofibrillar pores produced in swelling processes. The bending rigidity and bending hysteresis were decreased remarkly by liquid ammonia treatment. Therefore softness and dimensional stability were improved. The liquid amminia and NaOH/liquid ammonia-treated cottons moreover show excellent properties in tensile strength, anti-shrinkage for laundering, and wrinkle recovery.

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Durability of Fiber Reinforced Composites under Salt Water Environments (염수환경을 고려한 섬유강화 복합재의 내구성 평가)

  • Yoon Sung-Ho;Hwang Young-Eun
    • Proceedings of the KSR Conference
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    • 2005.05a
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    • pp.391-396
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    • 2005
  • Salt water spray test and salt water immersion test were experimentally conducted in order to investigate the durability of fiber reinforced composites under salt water environment. The specimens were made of glass fabric reinforcement and phenolic resin. Mechanical test was performed to obtain mechanical properties such as tensile properties, flexural properties, and shear properties by varying with exposure times. Also dynamic mechanical test and FTIR were conducted to investigate a change in chemical structure as well as thermal analysis properties such as storage shear modulus, loss shear moduls, and tan ${\delta}$. According to the results, salt water environment has effected on mechanical properties and thermal analysis properties and especially the durability of glass fabric/phenolic composites were severely affected on salt water immersion environment rather than salt water spray environment.

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A Study on the Modeling for Boom Structural Behaviors of the Triaxial Woven Fabric Composite (3-방향 직물 복합재료 모델링 및 붐 구조물의 거동 연구)

  • Seon-Woo, Byun;Ji-Yoon, Yang;Soo-Yong, Lee;Jin-Ho, Roh
    • Journal of Aerospace System Engineering
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    • v.16 no.6
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    • pp.99-105
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    • 2022
  • This paper studied the mechanical characteristics of boom structures by verifying the modeling method of representing unit cells of triaxial woven fabric (TWF) composites. The modeling of the representative unit cell obtained the ABD matrix by analysing the behaviour of tensile, shear, bending, and torsion using the periodic boundary conditions for the beam element. This study aimed to validate the ABD matrix by comparing the tensile analysis output from a finite element program with the experimental results from an MTS 810 machine. Additionally, the mechanical characteristics of a TWF composite boom structure were determined through bending analysis and experiments. The findings of this research are expected to be beneficial for developing structures using TWF composites.