Cyclic Behavior of Columns with Proposed Arrangement of Longitudinal Reinforcement
Journal
ACI Structural Journal
Journal Volume
122
Journal Issue
3
Start Page
147
End Page
159
ISSN
0889-3241
0889-3241
Date Issued
2025-05
Author(s)
Abstract
This research proposes a standardized arrangement of longitudinal reinforcement using Grade 690 MPa (100 ksi) high-strength steel and D32 (No. 10) or D36 (No. 11) large-diameter threaded bars to alleviate reinforcement congestion and construction difficulties. Four full-scale column specimens with the proposed standardized arrangement were tested using double-curvature lateral cyclic loading to examine their seismic performance. Test results showed that all the columns exhibited a combined axial and flexural failure mode, with ultimate drift ratios ranging from 4.07 to 5.98%, ratios of measured to nominal moment strength based on actual material strengths ranging from 1.18 to 1.51, and relative energy dissipation ratios satisfying the requirement of ACI 374.1-05. No shear or bond-splitting failures were observed. Based on the test data from this research and the literature, two modifications were proposed in the calculation of ℓd to relax the requirement of 1.25ℓd ≤ ℓu/2 as required by ACI 318-19.
Subjects
bond splitting
columns
high-strength reinforcement
large bar
longitudinal reinforcement
seismic
SDGs
Publisher
American Concrete Institute
Type
journal article