• 제목/요약/키워드: tear strength

검색결과 290건 처리시간 0.022초

지하 콘크리트 구조물의 거동에 대한 방수층의 대응성 평가에 관한 실험적 연구 (Performance Test Method on the Influence Waterproofing as Behavior of Concrete Structure)

  • 노종수;권시원;곽규성;권기주;오상근
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2004년도 학술대회지
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    • pp.77-81
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    • 2004
  • The massive structures are not free to move with vibration, differential settlement, thermal stresses because, construction and expansion joint, crack etc., can be large enough to cause leakage as deformation of waterproofing. It has been depended on the test method of tensile/tear strength which is waterproofing performance as behavior of concrete structure crack. However, not to practically confirm the creep applied to concrete surface, even waterproofing membrane have more performance than definite strength and elasticity. Therefore, in this study will focus on the test method to consider a resistance performance about loose adhesion and deformation of waterproofing and behavior of concrete structure as construction/expansion joint, crack. Performance test method on the influence as behavior of concrete structure crack is to choose waterproofing materials and construction method which possible to confront with behavior of 50mm crack in the atmosphere and low temperature. Examine the deformation of waterproofing membrane and loose adhesion which can occur to structure in general job site, suggest standard testing method to analyze correlation waterproofing membrane and structure with 5-types of materials used in this study, such as Adhesion membrane and sheet complex, sheet and urethane complex, self-adhesive sheet, spray poly-urea, spray membrane of rubberized Asphalt.

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유향수지 처리지의 물리 및 강도적 특성 (Physical and Strength Properties of Frankincense Resin Treatment Paper)

  • 김종민;윤승락;조종수
    • 펄프종이기술
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    • 제46권6호
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    • pp.26-33
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    • 2014
  • Frankincense resin was applied to Hanji to improve its physical properties. The resin-treated paper showed the increasement of physical properties such as weight, thickness, and density. The highest increasement in weight and density of resin-treated paper were found at 30% treatment concentrations and the largest values of density were $41g/m^2$ Hanji. With the increasement of concentration, the brightness was decreased and transparency was improved. Of the mechanical properties of the paper, the tensile index and burst index showed the improved values. The tear index, however, was decreased. The frankincense resin showed the highest result in the tensile index of resin-treated paper and the basis weight of $41g/m^2$ Hanji. The air resistance of the resin-treated paper got improved with the increase of the concentration and $105g/m^2$ Hanji showed the highest values. The highest improvement in air resistance may make the resin-treated Hanji possible to use for semipermeable materials.

열가소성 고무를 사용한 RUBBER SHEET의 제조 및 물성 (Development and Properties of Rubber Sheet using Thermoplastic Elastomer)

  • 천승한;한민현;문일식
    • Elastomers and Composites
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    • 제38권2호
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    • pp.122-127
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    • 2003
  • 환경에 유해한 PVC 재질의 바닥재나 시트를 대체하기 위하여 styrene-ethylene-butadiene-styrene(SEBS)과 같은 열가소성고무를 사용하고 polypropylene(PP) 등의 폴리머와 오일, 무기물 및 안정제 등을 혼합하여 내충격성 또는 탄성이 우수한 새로운 소재를 개발하기 위한 컴파운딩 연구를 진행하였다. SEBS와 오일의 혼합물에서 경도는 오일의 함량이 증가함에 따라서 선형적으로 감소하였고, SEBS/oil/PP의 조성물에서는 PP의 함량이 증가하면 인장강도는 선형적으로 증가하는 반면, 신율은 PP가 50phr상에서는 거의 영향이 없었다. PVC 소재의 바닥재나 시트를 대체 사용하기 위한 실질적인 SEBS 혼합물의 조성물에서도 인장 및 인열강도, 그리고 경도는 PP 함량에 비례하여 증가하는 것으로 나타났으나, 용융지수는 PP 함량이 증가하면 감소하는 것으로 나타났다.

Pot Life Assessment and Mechanical Property of Fast Curing Polyurethane Developed with Eco-friendly Pre-polymer

  • Joseph, Jessy;Moon, Junho;Kong, Tae Woong;Kim, Dong Ho;Oh, Jeong Seok
    • Elastomers and Composites
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    • 제55권1호
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    • pp.13-19
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    • 2020
  • 4,4'-Methylenebis(2-chlorobenzenamine) (MOCA)-free fast curing polyurethanes were prepared. In this study, the processibility of a fast curing polyurethane system was characterized by assessing the pot life. The obtained pot life of the polyurethane was 6-8 s, indicating that this prepolymer-curative system is appropriate for ribbon flow casting. The influence of the NCO index on the viscosity and mechanical properties was evaluated. The viscosity, tensile strength, tear strength, and hardness of the as-prepared polyurethanes showed an increasing trend, with an increase in the NCO index, whereas the elongation at break increased initially and then decreased with an increase in the NCO index. The gel fraction and crosslink density showed a direct correlation with the NCO index, which substantiated the improved mechanical properties at the higher NCO index. The coefficients of friction and abrasion deteriorated with an increase in the NCO index.

실험계획법을 이용한 전분/PVA 블렌드 제조 최적조건 탐구에 관한 연구 1. 다구찌 방법 (A Study on Optimal Conditions by means of Experimental Design for Preparation of Starch/PVA Blends 1. Taguchi method)

  • 이명석;홍영근
    • Elastomers and Composites
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    • 제40권2호
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    • pp.128-135
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    • 2005
  • 전분/PVA 블렌드의 기계적 물성에 영향을 미칠 수 있는 인자들을 고려하여 최적화 조건을 조사하였다. 실험은 다구찌 방법에 기반을 둔 실험크기 27, 3수준, 13열의 $L_{27}(3^{13})$ 직교배 열표가 사용되었다. UTM과 인열 강도계를 통하여 인장강도, 파단신율, 초기탄성률, 인열강도를 측정하여 전분/PVA 블렌드의 제조 최적 조건을 결정하였다. 각 변수들의 분석을 바탕으로 각인자의 상호작용 효과가 결정되었다. $L_{27}(3^{13})$의 분석결과, 글리세롤과 요소가 4가지 기계적 물성의 증진에 가장 중요한 인자로 파악되었다.

실험계획법을 이용한 전분/PVA 블렌드 제조 최적조건 탐구에 관한 연구 2, 다중혼합물 최적법 (A Study on the Optimal Conditions by Means of Experimental Design for Preparation of Starch/PVA Blends 2. Multiplex Mixture Optimal Method)

  • 홍영근;이명석
    • Elastomers and Composites
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    • 제41권1호
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    • pp.3-9
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    • 2006
  • 전분/PVA 블렌드의 기계적 물성에 영향을 미칠 수 있는 인자들을 고려하여 최적화 조건을 조사하였다. 통계적 방법인 다중혼합물 최적법을 사용하였으며, UTM과 인열 강도계를 통하여 블렌드의 인장강도, 파단신율, 초기모듈러스, 인열강도의 측정 결과를 분석하여 전분/PVA 블렌드의 제조 최적 조건을 결정하였다. 최적화 상태의 전분/PVA 블렌드는 농업용 필름의 기계적 물성 중 파단신율을 제외한 나머지 물성이 목표치와 같거나 조금 상회하는 수준을 나타내었다.

바이오 폴리올을 이용한 인공피혁 코팅용 폴리우레탄의 합성 및 특성 (Synthesis and Characterization of Polyurethane for Artificial Leather Using Bio Polyol)

  • 서석훈;최필준;고재왕;이재년
    • 한국염색가공학회지
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    • 제30권4호
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    • pp.321-328
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    • 2018
  • Wet polyurethane resin was synthesized by using polytrimethylene ether glycol prepared from 1,3-propanediol produced by fermentation from corn sugar as bio polyol and polyether-polyol(PTMG). Physical properties and cell characteristics by wet coagulation were investigated using the synthesized wet polyurethane resin. The tensile strength of wet polyurethane resin decreased with increasing content of bio polyol as copolymer polyol, but it tended to increase elongation at break and tear strength. As a result of thermal characteristic analysis, it was found that the glass transition temperature was slightly increased as the content of bio polyol increased. As a result of comparing the cell characteristics by the wet coagulation method, it was found that the shape of the cell was good when the ether polyol and the bio polyol were used alone.

피혁 폐기물을 재활용한 재생가죽의 내노화특성 연구 (A Study on Anti-Aging Properties of Recycled Leather Using Shaving Scrap by Applying Antioxidant)

  • 서은호;임성욱;이윤섭;김원주;박은영
    • 한국염색가공학회지
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    • 제35권3호
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    • pp.151-158
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    • 2023
  • In this study, we investigated the durability properties of the recycled leather using shaving scrap with antioxidant. Recycled leather sheets were manufactured by mixing shaving scrap and NB latex as a binder. HALS(Hindered Amine Light Stabilizer) and UVA(UV absorbers) were used as antioxidant. Mechanical properties such as hardness, tensile strength, elongation, tear strength and abrasion resistance were measured. Light aging resistance was evaluated using UV lamp and the degree of discoloration of the recycled leather sheets using a gray scale. In addition, to evaluate heat aging and UV aging, the degree of discoloration of the recycled leather sheets over time was measured using colorimeter. Washing fastness was evaluated on the degree of dyeing of recycled leather sheets for six type of multi-fiber woven fabrics (Acetate, Cotton, Nylon-66, Polyester, Acryl, Wool). To determine whether hazardous substances were detected in recycled leather sheets, the contents of arylamine and Cr 6+ were evaluated. As a result, when used in combination with antioxidant, the heat aging and light aging of recycled leather were improved and hazardous substance were not detected.

회전근 개 파열에 대한 관절경적 봉합술 중 일열 봉합술의 유용성 (Arthroscopic Rotator Cuff Repair by Single Row Technique)

  • 염재광
    • Clinics in Shoulder and Elbow
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    • 제11권2호
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    • pp.77-81
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    • 2008
  • 회전근 개 파열에 대한 봉합 수술의 목적은 봉합 초기에 고정력을 높이고 건-골 사이의 간격 형성을 최소화 하며 반복적인 부하에 기계적인 안정성을 유지시키고 회전근 개의 끝이 뼈에 부착되어 치유될 때까지 건-골 사이의 치유 환경을 최적화시키는 것이다. 일열 봉합은 원래의 회전근 개 부착부에 건을 완전히 부착시키는 면적이 제일 적고 간격 형성에 취약하다. 이열 봉합은 고정 실패를 방지하는 힘이 일열 봉합보다는 우수하고 간격 형성도 더 적으며 교량형 봉합은 최대 인장력이 가장 크며 전단력 및 회전력에 강하고 간격 형성도 제일 적다. 이러한 것을 볼 때 이열 봉합 및 교량형 봉합이 일열 봉합보다 우수한 점이 많지만 수술 시간이 좀 더 오래 걸리고 삽입하는 나사못의 개수도 많아 수술료가 비싸다는 단점도 가지고 있다. 따라서 일열 봉합도 회전근 개의 점액 낭측 부분층 파열이나 작은 완전 파열에 쓰여질 수 있는 아직은 유용한 방법으로 사료된다.

회전근개 파열 환자의 옷입고 벗기 향상을 위해 ICF Tool을 적용한 PNF 중재전략 : 증례보고 (A PNF Intervention Strategy with ICF Tool Applied for Improvement of Dressing in a Patient with Rotator Cuff Syndrome : A Case Report)

  • 김진철;이정아
    • 대한물리의학회지
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    • 제13권3호
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    • pp.49-60
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    • 2018
  • PURPOSE: This study was conducted to investigate the intervention effect obtained by applying an ICF tool to improve the dressing in a patient with rotator cuff syndrome to schematize the problems and approaching with PNF to solve the problems. METHODS: The subject of this study was a 44-year-old patient who underwent surgery after complete right rotator cuff tear. To treat his symptoms, the processes of clinical practice were implemented in the order of examination, assessment, diagnosis, prognosis, intervention, and outcome. During examination, patient information was collected using the ICF core set. In the assessment, the problems were schematized, and an ICF assessment sheet was used to identify the interaction of the problems. The diagnosis was made by clearly describing the causal relationship derived from the assessment in ICF terms. To solve the problems, the intervention was given in the order of indirect, direct, and task based on the philosophy of PNF. To evaluate the outcome, the differences before and after the intervention were compared. Additionally, the comparison for the ICF qualifier is presented with the ICF evaluation display. RESULTS: The results of the study showed clinical advantages in shoulder strength, eccentric control, range of motion, scapular stability, and shoulder pain. Overall, our patient with rotator cuff syndrome showed improvement in dressing and undressing activity in response to the PNF strategy. CONCLUSION: Application of the PNF intervention strategy after complete rotator cuff tear would have a positive effect on patient upper extremity function.