DOI QR코드

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Balanced Ratio of Concrete Beams Internally Prestressed with Unbonded CFRP Tendons

  • Lee, C. (School of Architecture and Building Science, Chung-Ang University) ;
  • Shin, S. (Graduate School, Chung-Ang University) ;
  • Lee, H. (Graduate School, Chung-Ang University)
  • 투고 : 2015.10.09
  • 심사 : 2016.09.28
  • 발행 : 2017.03.30

초록

The compression or tension-controlled failure mode of concrete beams prestressed with unbonded FRP tendons is governed by the relative amount of prestressing tendon to the balanced one. Explicit assessment to determine the balanced reinforcement ratio of a beam with unbonded tendons (${\rho}^U_{pfb}$) is difficult because it requires a priori knowledge of the deformed beam geometry in order to evaluate the unbonded tendon strain. In this study, a theoretical evaluation of ${\rho}^U_{pfb}$ is presented based on a concept of three equivalent rectangular curvature blocks for simply supported concrete beams internally prestressed with unbonded carbon-fiber-reinforced polymer (CFRP) tendons. The equivalent curvature blocks were iteratively refined to closely simulate beam rotations at the supports, mid-span beam deflection, and member-dependent strain of the unbonded tendon at the ultimate state. The model was verified by comparing its predictions with the test results. Parametric studies were performed to examine the effects of various parameters on ${\rho}^U_{pfb}$.

키워드

참고문헌

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피인용 문헌

  1. Performance Evaluation of CFRP Reinforced Concrete Members Utilizing Fuzzy Technique vol.12, pp.1, 2017, https://doi.org/10.1186/s40069-018-0313-0
  2. Calculating Method for Ultimate Tendon Stress in Internally Unbonded Prestressed Concrete Members vol.116, pp.5, 2017, https://doi.org/10.14359/51716764
  3. Comparative study of the flexural behavior of steel fiber-reinforced lightweight aggregate concrete beams reinforced and prestressed with CFRP tendons vol.233, pp.None, 2017, https://doi.org/10.1016/j.engstruct.2021.111901
  4. Feasibility and flexural behavior of RC beams prestressed with straight unbonded aluminum alloy tendons vol.24, pp.7, 2017, https://doi.org/10.1177/1369433220981662