Title:
Adapting Strut-and-Tie Modeling for Reinforced Concrete Curved Continuous Deep Box Girders
Author(s):
Khattab Saleem Abdul-Razzaq, Asala A. Dawood, and Wael Shawky Abdulsahib
Publication:
Structural Journal
Volume:
123
Issue:
2
Appears on pages(s):
225-240
Keywords:
deep box girders; horizontal curvature; reinforced concrete; shear; strut-and-tie model (STM); torsion
DOI:
10.14359/51749262
Date:
3/1/2026
Abstract:
The aim of the current research is to investigate the distinctive geometry of deep box girders under horizontal curvature. Six specimens were cast and tested to investigate the effect of both web and flange thickness and section height under horizontal curvature conditions. It was found that when using strut-and-tie modeling (STM) as is—that is, with the struts passing through both box girder webs—the results differed from the experimental data by 45 to 53%. However, when the STM was modified to include the influence of both flanges and the counteracting torsional shear resulting from the horizontal curvature on both webs, the results of the STM aligned more closely with the experimental results, reducing the difference to 7 to 32%. The shear generated by torsion had a minimal effect compared to the conventional shear, particularly due to the box girder’s geometry, especially when its span-to-effective depth ratio is low.
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