Computers and Concrete

  • 제6권2호
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  • Pages.167-185
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  • 2009
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  • 1598-8198(pISSN)
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  • 1598-818X(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Shrinkage movement analysis of reinforced concrete floors constructed in stages

  • Kwan, A.K.H. (Department of Civil Engineering The University of Hong Kong) ;
  • Ng, P.L. (Department of Civil Engineering The University of Hong Kong)
  • 투고 : 2007.11.28
  • 심사 : 2009.03.31
  • 발행 : 2009.04.25
⟨ 이전 논문 다음 논문 ⟩

초록

Reinforced concrete floors constructed between movement restraints often crack seriously due to shrinkage after completion. One common mitigation measure is to construct the concrete floors in stages to allow part of the shrinkage movement to take place before completion. However, shrinkage movement analysis of concrete floors constructed in stages is quite cumbersome, as the structural configuration changes during construction, thus necessitating reanalysis of the partially completed structure at each stage. Herein, a finite element method for shrinkage movement analysis of concrete floors constructed in stages is developed. It analyses the whole structure, including the completed and uncompleted portions, at all stages. The same mesh is used all the time and therefore re-meshing and location matching are no longer necessary. This is achieved by giving negligibly small stiffness to the uncompleted portions, which in reality do not exist yet. In the analysis, the locked-in strains due to increase in elastic modulus as the concrete hardens and the creep of the hardened concrete are taken into account. Most important of all, this method would enable fully automatic shrinkage movement analysis for the purpose of construction control.

키워드

참고문헌

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피인용 문헌

  1. Remnant creep based visco-elastic model for concrete creep analysis vol.168, pp.1, 2015, https://doi.org/10.1680/stbu.13.00028
  2. A rigorous analytical model for shrinkage cracking of reinforced concrete vol.69, pp.3, 2017, https://doi.org/10.1680/jmacr.16.00042
  3. Finite element analysis of concrete shrinkage cracks 2017, https://doi.org/10.1177/1369433217746346
  4. A model for the restrained shrinkage behavior of concrete bridge deck slabs reinforced with FRP bars vol.20, pp.2, 2009, https://doi.org/10.12989/cac.2017.20.2.215
  5. Analysis of Non-Uniform Shrinkage Effect in Box Girder Sections for Long-Span Continuous Rigid Frame Bridge vol.13, pp.2, 2009, https://doi.org/10.7250/bjrbe.2018-13.409