Title:
Effects of Slabs Characteristics on Long-Term Deflections of One-Way Reinforced-Concrete Slabs
Author(s):
John E. Ardila-Gonzalez, Matías A. Hube, and Julian Carrillo
Publication:
Structural Journal
Volume:
123
Issue:
3
Appears on pages(s):
33-44
Keywords:
creep; deflections; long-term; one-way slab; serviceability, shrinkage.
DOI:
10.14359/51749488
Date:
5/1/2026
Abstract:
Controlling deflections in reinforced concrete (RC) flexural members under service loads is a serviceability requirement prescribed by design codes, such as ACI CODE-318. Serviceability requirements are challenged by productivity requirements, such as faster construction and longer span demands, among others. This paper summarizes a parametric analysis conducted to estimate long-term deflections of one-way RC slabs. The objective of this study is to assess the effect of geometrical, concrete, and construction parameters on the long-term deflections of one-way RC slabs. The effect of these parameters on immediate deflections is also analyzed. Results of this study show that increasing the slab thickness and the area of tension reinforcement proved to be the most effective strategies for reducing both immediate and long-term deflections of one-way RC slabs. Additionally, the results of the parametric study highlight the relative influence of each studied parameter in controlling deflections.
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