• 제목/요약/키워드: pressure tubes

검색결과 652건 처리시간 0.06초

Efficiency of stiffening plates in fabricated concrete-filled tubes under monotonic compression

  • Albareda-Valls, Albert;Carreras, Jordi Maristany
    • Steel and Composite Structures
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    • 제18권4호
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    • pp.1023-1044
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    • 2015
  • Concrete-filled tubes (CFT), formed by an outer steel tube filled with plain or reinforced concrete inside, have been increasingly used these recent decades as columns or beam-columns, especially for tall buildings in seismic areas due to their excellent structural response. This improved behavior is derived from the effect of confinement provided by the tube, since the compressive strength of concrete increases when being subjected to hydrostatic pressure. In circular CFTs under compression, the whole tube is uniformly tensioned due to the radial expansion of concrete. Contrarily, in rectangular and square-shaped CFTs, the lateral flanges become subjected to in-plane bending derived from this volumetric expansion, and this fact implies a reduction of the confinement effect of the core. This study presents a numerical analysis of different configurations of CFT stub columns with inner stiffening plates, limited to the study of the influence of these plates on the compressive behavior without eccentricity. The final purpose is to evaluate the efficiency in terms of strength and ductility of introducing stiffeners into circular and square CFT sections under large deformation axial loading.

알루미늄 튜브의 열처리 조건에 따른 액압 성형성 연구 (Effects of Heat Treatment on Hydroformability of Aluminum Tubes)

  • 이문용;손성만;조완제;이상용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2001년도 추계학술대회 논문집
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    • pp.364-367
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    • 2001
  • Recently social demands of fuel economy and environmental regulation require the development of light materials and new manufacturing technologies. In this point, aluminum tube hydroforming, which is satisfied with good strength-to-weight ratio and recyclability, is new innovative concept. but, up to now the level of that is relatively low. In this paper, we studied formability of different aluminum tubes in different heat treatments under internal pressure and axial feeding, and mechanical properties of aluminum tubes before and after hydroforming.

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R407C 및 R290 냉매에 대한 모세관내 유동특성 실험 및 모델링 (Experimentation and modeling on the flow of R407c and R290 through capillary tubes)

  • 김용찬;조일용;최종민
    • 설비공학논문집
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    • 제11권4호
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    • pp.492-498
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    • 1999
  • Mass flow rates of R407C and R290 through capillary tubes were measured with various capillary tube geometries and flow conditions. For all refrigerants tested in the present study, mass flow rate through the capillary tube was strongly dependent on the condensing pressure, subcooling and capillary length and diameter. The flow rate of R407C was 5~10[%] higher than that of R22 at the same condensing temperature and degree of subcooling, while flow rate for R290 was 40[%] lower than that for R22. Based on experimental results, an empirical correlation was developed using Pi theorem to predict the mass flow rate through capillary tubes. The predicted flow rates using the model were consistent with the experimental data within ${\pm}$10[%].

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