Title:
Effective Moment of Inertia and Slenderness Limits of Reinforced Concrete and Fiber-Reinforced Concrete Slabs
Author(s):
Nikola Tosic, Marc Sanabra-Loewe, Alejandro Nogales, and Albert de la Fuente
Publication:
Structural Journal
Volume:
119
Issue:
5
Appears on pages(s):
227-240
Keywords:
DOI:
10.14359/51734666
Date:
9/1/2022
Abstract:
Following the trend of updating methods that establish the minimum slenderness of concrete members based on the work by Rangan and Scanlon, this paper elaborates new formulations of the effective moment of inertia factor (α), which expresses the ratio of the equivalent moment of inertia to the gross moment of inertia. For this purpose, closed-form solutions for α in reinforced concrete (RC) and fiber-reinforced concrete (FRC) one-way members are derived. Further, a parametric study is carried out to evaluate the relationship of the neutral axis position in RC and FRC members with equal longitudinal reinforcement ratios. Additionally, a simplified equation is proposed for the neutral axis position in FRC members. Based on experimental and numerical data on deflections of FRC members, the expression for the effective moment of inertia is adjusted. Finally, a comparison between α factors for RC and FRC members is presented and implications for minimum thicknesses of members are discussed.
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