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An Analysis on Short and Long-Term Deflections of Flat Plates Considering Construction and Design Conditions

시공 및 설계조건을 고려한 플랫 플레이트의 장단기 처짐 분석

  • Received : 2012.05.14
  • Published : 2012.08.25

Abstract

The structural design or construction plan of RC flat plates may be governed by serviceability conditions. Specially, since over-loading and tensile cracking in early-aged slabs significantly decrease the serviceability of a flat plate system under construction, construction conditions and their impacts on the slab deflections may be decisive factors in planning flat plate systems. In this study, the parametric study for short and long-term deflections of flat plates was performed. For various design and construction conditions of the number of shore floors, a slab construction cycle, a distance among shores, a section area of shore, a concrete strength, a compressive reinforcement ratio, a tensile reinforcement ratio, and a slab thickness, the construction loads were calculated by considering shore stiffness and concrete cracking as well as slab stiffness and construction steps, and then the immediate deflections at construction stages and long-term deflections at service stages were calculated. The effects of each design or construction condition on the control of short and long-term deflections were analyzed.

Keywords

Acknowledgement

Supported by : 한국연구재단

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