Title:
Update to Shear Strength Provisions for Concrete Columns in ACI CODE-369.1-22
Author(s):
Ariel A. Suselo, Wassim M. Ghannoum, and Adolfo B. Matamoros
Publication:
Structural Journal
Volume:
122
Issue:
4
Appears on pages(s):
245-256
Keywords:
cyclic loadings; diagonal tension; rectangular concrete columns; shear strength; short columns; slender columns; strut-and-tie; truss model.
DOI:
10.14359/51745487
Date:
7/1/2025
Abstract:
This paper presents important revisions to the shear strength provisions for seismic assessment of reinforced concrete columns in
ACI CODE-369.1-22. A new formulation based on a strut-and-tie
model is introduced to expand the range of application of existing
provisions to include columns with shear span-depth ratios lower
than 2. Revisions are proposed to the slender column provisions
to improve their precision, reduce estimate bias, and eliminate
instances where they produce unconservative estimates of shear
strength. The proposed relations were calibrated using shear
strength data from 94 shear-critical rectangular columns subjected
to load reversals from a database developed at The University of
Texas at San Antonio.
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