Title:
Curved Strut-and-Tie Recognition in Reinforced Concrete Elliptical Deep Beams
Author(s):
Khattab Saleem Abdul-Razzaq, Baidaa N. Hasan, and Asala A. Dawood
Publication:
Structural Journal
Volume:
122
Issue:
1
Appears on pages(s):
183-197
Keywords:
elliptical ring deep beams; flexural reinforcement; proposed mathematical model; reinforced concrete; strut-and-tie method (STM); web reinforcement.
DOI:
10.14359/51742152
Date:
1/1/2025
Abstract:
Elliptical deep beams have a peculiarity: the compression paths
(struts) are neither straight nor symmetrical within the same span.
The asymmetrical horizontal curvature in one span leads to the
formation of asymmetrical torsional moments. The strut-and-tie
method (STM), approved by ACI 318-19 and most international
codes, does not take into consideration the curvature of the strut
and the consequent bending and torsional moments. Therefore,
eight deep elliptical specimens were cast and reinforced with variable amounts of web and flexural reinforcement to study the role and importance of each one experimentally and theoretically from the STM point of view. Only the stress paths were cast and reinforced in two other specimens to study the STM in detail and to
present alternative specimens to the reference ones with less weight
and cost, in addition to providing openings for services. The STM
has proven its effectiveness with asymmetrical, horizontally curved
deep beams due to its ease and the high safety it provides. STM
development has also been presented here by adding the effect of
the horizontal curvature.
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