• 제목/요약/키워드: Durability of Abrasion

검색결과 111건 처리시간 0.027초

강섬유 보강 EVA 콘크리트의 역학적 특성 및 내마모성 (Mechanical Properties and Durability of Abrasion of EVA Concrete Reinforced Steel Fiber)

  • 성찬용;남기성
    • 한국농공학회논문집
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    • 제56권5호
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    • pp.45-54
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    • 2014
  • This study was performed to evaluate compressive strength, flexural strength, static modulus of elasticity, stress-strain ratio and durability of abrasion on EVA concrete reinforced steel fiber (SF) in order to use hydraulic structures, underground utilities, offshore structures and structures being applied soil contaminated area. It is used ordinary portland cement, crushed coarse aggregate, nature fine aggregate, EVA redispersible polymer powder, superplasticizer and deforming agent to find optimum mix design of EVA concrete reinforced steel fiber. EVA concrete reinforced SF was effected on the improvement of mechanical properties and durability of abrasion.

콘크리트 구조체 내구성 향상을 위한 침투성 표면 보호재의 특성에 관한 실험적 연구 (An Experimental Study about Characteristics of Penetrating Surface Protection Materials to Promote Concrete Structure Durability)

  • 이정윤;조병영;김영근;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2005년도 추계 학술논문 발표대회
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    • pp.93-96
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    • 2005
  • Concrete has been considered as a semi-permanent structural material, because its excellent durability. Recently, durability decline of concrete construction by environmental pollution is becoming social problem. The durability of high durable structure is declined by carbonate, chloride permeation and deterioration of waterproof performance, etc. This study of penetrating surface protection materials evaluated about carbonation, chloride permeation, waterproof performance, and durability of abrasion, etc. It is profitable in durability that spread penetrating surface protection materials

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굵은 골재의 관한 연구 (A Study of Abrasion Rate of Coarse Aggregate)

  • 이동영;전현우
    • 한국농공학회지
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    • 제12권3호
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    • pp.2013-2018
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    • 1970
  • Abrasion rate of coarse aggregates is an important factor to determine aggregates quality. Allowable limit of abrasion rate of coarse aggregates for concrete is 40% according to K.S. Strength and durability test of concrete with 19 efferent aggregates were made. From this test, it was found that allowable limit of abrasion rate of aggregates can be increased to 43%.

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조기강도 콘크리트의 내구특성 (Durability Characteristics of High-Early-Strength Concrete)

  • 원종필;김현호;안태송
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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    • pp.991-996
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    • 2001
  • The long-term durability characteristics of high-early-strength concrete were assessed. The effect of long-term durability characteristics of high-early-strength concrete were investigated. In experiment, two different types of fiber were adopted for improvement of durability. High-early-strength fiber reinforced concretes using regulated-set cements are compared with high-early-strength concrete without fiber. The durability performance of the laboratory-cured high-early-strength concrete specimens was determined by conducting an accelerated chloride permeability, abrasion resistance, freeze-thaw, surface deicer salt scaling and wet-dry repetition test. The results indicated that incorporation of fibers enhance durability performance.

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유가증권 인쇄용 감광성 수지 볼록판의 내마모성 및 화선 재현에 관한 연구 (The Study of Resistant Abrasion and Image Reproduction of the Photosensitive Plastic Convex Printing Plate for Securities Printing)

  • 김병현;강영립;이혁원
    • 한국인쇄학회지
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    • 제29권3호
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    • pp.55-63
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    • 2011
  • The convex printing plate in particular securities is classified three physical properties. The main ingredient(component)of photosensitive plastic is composed of thermosetting polyamide. After being hardened specimen at $80^{\circ}C$ is shown to resist highly, the Glass Transition Temperatures of photosensitive plastic are $85^{\circ}C$. When hardened plate has reached at $80^{\circ}C$, abrasion loss is minimized. the cause is considered it is more effective in hardening when the temperature of photosensitive plastic is $80^{\circ}C$-the vitrification temperature of those. The hardness and the durability of the convex printing plate in particular securities are affected to the hardening treatment temperature. And the resolution of original drawing has being better when the durability is superior.

반복신장 및 마모강도시험을 통한 봉제방법에 따른 스테인리스 스틸 전도사의 내구성 평가 (Durability Evaluation of Stainless Steel Conductive Yarn under Various Sewing Method by Repeated Strain and Abrasion Test)

  • 정임주;이선희
    • 한국의류학회지
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    • 제42권3호
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    • pp.474-485
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    • 2018
  • Smart sensors and connected devices have changed the concept of garments along with IT technology convergent garments that transform the performance of basic functions. Various types of products have been researched and developed due to the increased interest in smart clothing; in addition, studies based on physical and mechanical properties have also been actively studied to improve accuracy and reliability. This study represents a basic study for the development of smart textiles based on motion recognition for the surfing practice of beginners interested in IT convergence type. A physical durability evaluation of conductive yarn according to sewing method was later carried out. This study is a conditional specimen sewn with cotton lower thread and 100mm pattern length based on the results of previous studies. The durability of the conductive yarn according to the sewing method was evaluated according to the sewing method. Durability was evaluated by two kinds of repeated strain and abrasion tests. The specimen with applied cotton in a lower thread zigzag pattern 2mm stitch size 100mm stitch length was shown to have the most suitable durability for smart textile.

Physical, Mechanical and Durability Properties of the Quartzite Units of Central Nepal Lesser Himalaya

  • Dinesh Raj Sharma;Naresh Kazi Tamrakar;Upendra Baral
    • 지질공학
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    • 제34권1호
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    • pp.67-105
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    • 2024
  • This study compares the quartzites of four quartzite units: The Fagfog Quartzite, Dunga Quartzite (member of the Robang Formation), Pandrang Quartzite (member of the Kalitar Formation) and the Chisapani Quartzite. The analysis shows variations in flakiness and elongation, as the Fagfog Quartzite displays low flakiness whereas the Pandrang and the Chisapani have moderate and the Dunga Quartzite has shown variations. The density values of the four quartzite units remain consistent, indicating uniform physical properties and porosity levels. However, bulk density values differ among the quartzites, suggesting variations in particle arrangement, porosity, and density. Regarding strength measures, the Pandrang and the Chisapani Quartzite have higher strength characteristics as compared to the Fagfog and the Dunga Quartzites. The Pandrang Quartzite has the highest average point load strength index, classifying it as "Extremely Strong". The resistance to impact and crushing forces varies among the quartzites, with lower Aggregate Impact Value (AIV) and Aggregate Crushing Value (ACV) indicating higher strength and durability. Durability tests show that the Fagfog Quartzite has high durability against slaking, with a slight decrease observed after the fifth cycle. The Dunga Quartzite shows varying degrees of weathering, while the Pandrang and the Chisapani Quartzite have minimal weight changes, indicating strong resistance to weathering. Magnesium sulfate soundness tests indicate high durability and resistance to degradation for all four units. The Los Angeles abrasion value (LAAV) tests indicate favorable resistance to abrasion for the majority of the Fagfog, Dunga, and the Pandrang Quartzites samples, while Chisapani Quartzite shows more variability in LAAV values. The Pandrang Quartzite shows a higher proportion of elongated particles but lower flakiness index values as compared to Fagfog and Dunga Quartzites while Chisapani Quartzite stands out with a significantly higher presence of flaky particles and lower elongation index values. Mechanically, the Fagfog and Dunga Quartzite show higher strength and better resistance to abrasion and freeze and thaw. The Pandrang Quartzite shows moderate resistance to crushing and sudden effect, while the Chisapani Quartzite has variable resistance to effect. This comparative study emphasizes the diversity and complexity of quartzite rock types, showing the need for comprehensive characterization and assessment to determine their suitability for specific applications.

차수벽 콘크리트의 균열제어 및 성능향상에 관한 연구 (Control of Crack and Enhanced Durability Performance of Face Slab Concrete)

  • 임정열;정우성;김완영;원종필
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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    • pp.537-540
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    • 2003
  • The effects of substituting cement with fly ash(10%, 15%, 20%) and different fiber addition(polypropylene, cellulose, poly vinyl alcohol), on the control of microcrack and enhanced durability performance of face slab concrete in CFRD was studied experimentally It was conducted experiments of plastic shrinkage of mortar and concrete, and drying shrinkage of concrete. Also, durability test were carried out the chloride permeability, abrasion resistance and freeze-thaw repetition. Through the experimental results, it was concluded that ploy vinyl alcohol fiber containing concrete was the most effective mixture in control of cracking and durability.

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강섬유보강 콘크리트의 내구성 및 건조수축변형 특성에 관한 실험적 연구 (An Experimental Study on the Durability and Dryng Shrinkage of Steel Fiber Reinforced Concrete)

  • 박승범;윤의식;홍석주;박병철
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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    • pp.80-83
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    • 1995
  • In order to develope and apply high-performance steel fiber reinforced concrete (SFRC), the effects of steel fibers on durability and long-term deformation of SFRC due to various mixing conditions have been studied. As the test result show, the manufacturing process technology of industrial SFRC is developed And the durability of SFRC such as freeze-thaw, resisteance abrasion resistance are significantly improved, the drying shrinkage of SFRC, is remarkably decreased by increasing the steel fiber contents than plain concrete

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내마모성을 갖는 고속 분립체 이송용 곡관의 형상 설계 (Design of Anti-abrasive curved ducts for high-velocity gas-solid flow)

  • 권동구;김윤제
    • 한국에너지공학회:학술대회논문집
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    • 한국에너지공학회 2000년도 춘계 학술발표회 논문집
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    • pp.229-235
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    • 2000
  • A study on the improvement of anti-abrasion nature of curved ducts for high-velocity gas-solid flow which are typically equipped in a coal-burned steam power plant has been investigated numerically and experimentally. To reduced the abrasion of pipe by particle, we have tried to form the vortex flow field in the region where flow changes its direction , modelled with two different shapes. 22.5$^{\circ}$and 90$^{\circ}$ elbows. the governing equations for three -dimensional , turbulent flow fields are discretized by FVM and solved bySIMPLE algorithm . From the numerical analysis, the new designed elbows for reducing abrasion have been developed. Numerical results are compared with the experimental abrasion data which are obtained from one of the operating coal burned steam power plants in Korea. Comparison of these results show that the developed elbows have much more durability than the original one.

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