Journal of Korean Society of Steel Construction (한국강구조학회 논문집)

Korean Society of Steel Construction (한국강구조학회)
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Experimental Verification of Age-adjusted Effective Modulus Method to Long-Term Behavior Estimation of Prestressed Composite Girders

재령보정 유효계수방법에 의한 프리스트레스트 합성거더의 장기거동 실험 검증

  • Bae, Doo-Byong (School of Civil and Environmental Engineering, Kookmin University) ;
  • Oh, Chang-Kook (School of Civil and Environmental Engineering, Kookmin University) ;
  • Choi, Sok-Hwan (School of Civil and Environmental Engineering, Kookmin University)
  • 배두병 (국민대학교, 건설시스템공학부) ;
  • 오창국 (국민대학교, 건설시스템공학부) ;
  • 최석환 (국민대학교, 건설시스템공학부)
  • Received : 2011.05.13
  • Accepted : 2012.08.14
  • Published : 2012.10.27
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Abstract

Prestressed composite girders provide efficient composite action by applying prestress to the sub-encasing concrete. In this study, an enhanced prestressed composite girder with forms suspended from the steel girder is utilized. Long-term behavior of the prestressed composite girder is estimated using age-adjusted effective modulus method, which is verified experimentally using measurements obtained from an in-service bridge. Then, parametric study is carried out to investigate the influences caused by ambient temperature, humidity, prestressing and concrete casting date.

프리스트레스트 합성거더란 합성거더의 하부 콘크리트에 프리스트레싱 강선을 통해 압축력을 도입한 거더형식으로, 본 연구에서는 거푸집을 강재에 매달아 콘크리트의 자중이 강재에 부담된 상태로 합성시켜 단면의 효율을 극대화한 거더를 사용하였다. 이러한 프리스트레스트 합성거더에 대하여 재령보정 유효계수방법을 사용하여 시공단계별로 발생하는 여러 지속하중에 의한 장기거동 효과로 인해 유발되는 프리스트레스의 손실을 산정하고, 실제교량을 대상으로 시공단계별로 계측한 결과에 대해 야쓰미해법을 이용한 결과와 비교하였고, 또한 온도, 습도, 프리스트레스 긴장시기, 바닥판 타설시기를 변수로 한 변수해석을 수행하여 유효성을 검증하였다.

Keywords

References

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Cited by

  1. Improvement in Long-term Behavior Estimation of Prestressed Composite Girders for Various Construction Sequences using Parametric Study vol.25, pp.4, 2013, https://doi.org/10.7781/kjoss.2013.25.4.369