Structural Engineering and Mechanics

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Effect of fiber reinforcing on instantaneous deflection of self-compacting concrete one-way slabs under early-age loading

  • Vakhshouri, Behnam (Faculty of Engineering and Information Technology, School of Civil and Environmental Engineering, University of Technology Sydney) ;
  • Nejadi, Shami (Faculty of Engineering and Information Technology, School of Civil and Environmental Engineering, University of Technology Sydney)
  • Received : 2017.01.07
  • Accepted : 2018.05.04
  • Published : 2018.07.25
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Abstract

The Early-age construction loading and changing properties of concrete, especially in the multi-story structures can affect the slab deflection, significantly. Based on previously conducted experiment on eight simply-supported one-way slabs this paper investigates the effect of concrete type, fiber type and content, loading value, cracking moment, ultimate moment and applied moment on the instantaneous deflection of Self-Compacting Concrete (SCC) slabs. Two distinct loading levels equal to 30% and 40% of the ultimate capacity of the slab section were applied on the slabs at the age of 14 days. A wide range of the existing models of the effective moment of inertia which are mainly developed for conventional concrete elements, were investigated. Comparison of the experimental deflection values with predictions of the existing models shows considerable differences between the recorded and estimated instantaneous deflection of SCC slabs. Calculated elastic deflection of slabs at the ages of 14 and 28 days were also compared with the experimental deflection of slabs. Based on sensitivity analysis of the effective parameters, a new model is proposed and verified to predict the effective moment of inertia in SCC slabs with and without fiber reinforcing under two different loading levels at the age of 14 days.

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References

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