• 제목/요약/키워드: EYM (European Yield Model)

검색결과 3건 처리시간 0.022초

Evaluation of Strength Properties for Bolted Connections with Lumber from Small Diameter Logs

  • Park, Joo-Saeng;Park, Chun-Young;Chun, Su-Kyoung;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
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    • 제30권3호
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    • pp.59-65
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    • 2002
  • EYM (European Yield Model), which was adopted in NDS (National Design Specification for wood construction), has been used in Korea without any verification of the analysis of bolted wood connections. In the case of applying lumber from domestic small diameter logs, however, there are some problems with the direct application of EYM ; 1) relatively low dowel bearing strength and dimensional stability due to a large amount of immature wood, 2) effect of MC (moisture contents) on the dowel bearing strength of wood and the yield load of a bolted connection. To evaluate the strength properties of bolted connections with lumber from domestic small diameter logs, effect of MC on the dowel bearing strength of wood was investigated and double shear bolted connection tests were performed. As the MC of wood increased, the dowel bearing strength was linearly reduced, even under 19% MC, which showed that adjustment, not considered in NDS, was required. Double shear bolted connection tests indicated that effect of MC on yield load should be considered in order to determine design value.

Shear Performance of Wood-Concrete Composite II - Shear Performance with Different Anchorage Length of Steel Rebar in Concrete -

  • Lee, Sang-Joon;Eom, Chang-Deuk;Kim, Kwang-Mo
    • Journal of the Korean Wood Science and Technology
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    • 제40권5호
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    • pp.327-334
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    • 2012
  • Wood and concrete show significantly different physical properties, and it need to be firstly understood for using wood-concrete composite. This study is performed for compensating this and effective hybridization of wood and concrete. This research in planned for wood-concrete composite after previous research which deals the shear performance with different anchorage length of steel rebar in wood. Yield mode and reference design value (Z) were derived using EYM (European Yield Model). And the yield mode changed before and after anchorage length of 10~15 mm - $I_s$ mode to IV mode. There was not increasing tendency of shear performance with increased anchorage length for over 20 mm of anchorage in concrete. And wood composite shows 65% and 93% on initial stiffness and yield load respectively compared with the wood-concrete composite. Wood-concrete composite showed brittle failure after yield point while wood-to-wood composite showed ductile failure.

낙엽송 부재의 이중 전단 볼트 접합부 강도 성능 (Strength Property of Double Shear Bolted-Connections of Larch)

  • 박천영;김광모;이전제
    • Journal of the Korean Wood Science and Technology
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    • 제33권1호통권129호
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    • pp.7-16
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    • 2005
  • 본 연구에서는 국산 낙엽송 부재를 이용한 이중 볼트 전단 접합부의 성능을 평가하였다. 주부재로 두께 39 mm, 89 mm, 139 mm, 189 mm로 제재된 국산 낙엽송 제재목과 국산 낙엽송으로 제조된 두께 80 mm, 140 mm, 170 mm 집성재를 사용하였으며, 측면 부재로는 동일 두께의 제재목과 6 mm 철판을 사용하였으며, 접합 철물로는 M12, M16, M20 볼트를 사용하였다. 접합부에 대한 하중 방향은 주부재와 측면 부재의 목리 경사에 대해 수직, 수평한 경우에 대하여 실시하였다. 다우얼 지압 강도 실험을 통해 부재의 다우얼 지압 강도를 산출하고, 볼트 휨 실험을 통해 볼트의 휨 강도를 구한뒤, 최종 볼트 접합부 실험을 통해 접합부 성능을 평가하였으며, 최종 결과는 EYM (European Yield Model)을 사용한 계산값과 비교 평가하였다. 연구 결과 국산 낙엽송 부재의 이중 전단 볼트 접합부 성능은 EYM을 사용하여 얻어진 계산값과 비교하였을 때 그에 상응하거나 그 이상임을 알 수 있었으며, 특히 측면 부재가 제재목인 경우는 거의 일치함을 알 수 있었다. 파괴 모드는 옹이나 건조 결함 등의 영향을 많이 받으며 주부재의 두께가 작을 경우는 mode I, 주부재가 커짐에 따라 mode III으로 옮겨감을 알 수 있었다.