Title:
Effective Moment of Inertia of Reinforced Concrete and Reinforced Steel Fiber-Reinforced Concrete One-Way Slabs
Author(s):
Jung Lee, Kyungchan Kim, Chadon Lee, and Songhee Lee
Publication:
Structural Journal
Volume:
121
Issue:
6
Appears on pages(s):
19-32
Keywords:
deflection; design code; effective moment of inertia; fiberreinforced concrete; serviceability; slab
DOI:
10.14359/51740850
Date:
11/1/2024
Abstract:
An effective moment of inertia (Ie) unified for reinforced concrete
(RC) and reinforced steel fibrous concrete (RSFC) one-way slabs
was presented. Two model parameters for the degree of tension
stiffening and plasticization of concrete in compression (PZC),
where the relationships of concrete stresses and strains deviate
from its linear elastic stage, were calibrated using 26 test results
of RC and RSFC slabs, including eight slabs tested in this study
for three different reinforcement ratios (ρ) and fiber contents
(Wf). Comparisons with test results revealed that underestimated
deflections were predicted with the Ie currently adopted as basic
formats in different codes, for RC slabs having relatively lower or
higher ρ values and RSFC slabs with wide ranges of ρ typical to
one-way slabs. However, regardless of the magnitudes of ρ and Wf,
reasonable deflections were predicted with the unified Ie, which was
constituted with linearized weight functions of the ratio of cracking
moment to moment in service and modified to include the effects of
ρ, PZC, and Wf.
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