Title:
Design Tool for Finding Minimum Heights of Reinforced Concrete Beams and One-Way Slabs
Author(s):
Marc Sanabra-Loewe, David Garcia, Nikola Tosic, and Albert de la Fuente
Publication:
Structural Journal
Volume:
121
Issue:
3
Appears on pages(s):
43-56
Keywords:
beam; deflection control; maximum slenderness; one-way solid slab; reinforced concrete (RC); serviceability; stiffness
DOI:
10.14359/51740458
Date:
5/1/2024
Abstract:
Finding the minimum height of reinforced concrete (RC) slabs and
beams at the early stages of design is critical for efficient material
use. Hence, methods are needed for determining the maximum
slenderness, L/h, that are both easy to use and able to consider as
many influencing factors as possible, given that deflection typically
controls the design of this kind of structure. One such method is
the “long method of Rangan-Scanlon,” with recent advances in
new closed-form solutions enabling direct calculation. This study
builds on those advances, presenting a parametric study for RC
beams and one-way slabs to determine the effect of key factors
(compressive strength of concrete, reinforcement cover, span, tributary width, load, and boundary conditions) on the effective moment of inertia factor α and slenderness L/h. The results provide practical design tools for determining the maximum slenderness of RC one-way slabs by previously finding the α factor and directly determining the maximum slenderness for RC beams.
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