Title:
Behavior of Concrete Columns with Double-Head Studs Under Earthquake Loading: Parametric Study
Author(s):
Samer A. Youakim and Amin Ghali
Publication:
Structural Journal
Volume:
100
Issue:
6
Appears on pages(s):
795-803
Keywords:
column; confinement; crossties; ductility; stud.
DOI:
10.14359/12846
Date:
11/1/2003
Abstract:
The experimental results of six column specimens laterally reinforced with double-head studs under simulated-earthquake loading are presented. The columns have a cross section of 250 x 500 mm and a height of 1500 mm, and they are laterally loaded to bend about their weak axis. The specimens are tested under constant axial load level combined with incrementally increasing lateral displacement reversals. The test variables include axial load level, spacing and volumetric ratio of transverse reinforcement, and distribution of longitudinal bars around the core perimeter and the resulting tie configuration. The applied axial load was 20 or 30% of the nominal axial capacity of the columns. The requirements for the amount and the detailing of confinement reinforcement in columns according to the seismic provisions of the ACI 318-02 Code as well as other design approaches are evaluated using the experimental results. It is concluded that, for this range of axial load levels, the requirements of the ACI Code are overly conservative, and that increasing the volumetric ratio of transverse reinforcement results in modest enhancement in the ductility of columns.