Structural Engineering and Mechanics

  • 제69권1호
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  • Pages.1-10
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  • 2019
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Minimum thickness of flat plates considering construction load effect

  • Hwang, Hyeon-Jong (College of Civil Engineering and Hunan Provincial Key Lab on Damage Diagnosis for Engineering Structures, Hunan Univ.) ;
  • Ma, Gao (College of Civil Engineering and Hunan Provincial Key Lab on Damage Diagnosis for Engineering Structures, Hunan Univ.) ;
  • Kim, Chang-Soo (School of Architecture, Seoul National University of Science and Technology)
  • 투고 : 2018.03.22
  • 심사 : 2018.11.29
  • 발행 : 2019.01.10
⟨ 이전 논문 다음 논문 ⟩

초록

In the construction of flat plate slabs, which are widely used for tall buildings but have relatively low flexural stiffness, serviceability problems such as excessive deflections and cracks are of great concern. To prevent excessive deflections at service load levels, current design codes require the minimum slab thickness, but the requirement could be unconservative because it is independent on loading and elastic modulus of concrete, both of which have significant effects on slab deflections. In the present study, to investigate the effects of the construction load of shored slabs, reduced flexural stiffness and moment distribution of early-age slabs, and creep and shrinkage of concrete on immediate and time-dependent deflections, numerical analysis was performed using the previously developed numerical models. A parametric study was performed for various design and construction conditions of practical ranges, and a new minimum permissible thickness of flat plate slabs was proposed satisfying the serviceability requirement for deflection. The proposed minimum slab thickness was compared with current design code provisions and numerical analysis results, and it agreed well with the numerical analysis results.

키워드

과제정보

연구 과제 주관 기관 : National Natural Science Foundation of China

참고문헌

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피인용 문헌

  1. Critical thrust force and feed rate determination in drilling of GFRP laminate with backup plate vol.73, pp.6, 2019, https://doi.org/10.12989/sem.2020.73.6.631