Journal of Korean Association for Spatial Structures (한국공간구조학회논문집)

Korean Association for Spatial Structures (한국공간구조학회)
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Stress of External Steel Rod in Post-Tensioned Concrete Beam

포스트텐션 콘크리트 보에서 비부착 외부강봉의 응력

  • Lee, Swoo-Heon (University of Texas at Arlington) ;
  • Kang, Thomas H.K. (Dept. of Architecture & Architectural Engineering, Seoul National University) ;
  • Shin, Kyung-Jae (School of Architecture & Architectural Engineering, Kyungpook National University)
  • Received : 2014.05.21
  • Accepted : 2014.07.15
  • Published : 2015.03.15
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Abstract

This paper shows the simplified equation to predict the ultimate moment capacity and corresponding rod stress in reinforced concrete beam with external post-tensioning rods. Because the stress of external post-tensioning rod depends on the beam deflection, the previous analytical model for post-tensioned beams requires a tedious iteration process. Also, the stress equations in ACI code or other researchers' models are suitable only for internal tendons in concrete beams. In this study, given the lack of analytical approaches to predict the nominal stress of the external unbonded rod, a simple and robust equation has been proposed for externally post-tensioned concrete beams. It is concluded that the proposed equation predicted the stress of external steel rods in post-tensioned concrete beams reasonably well.

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References

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