Title:
High-Strength Concrete Columns under Simulated
Earthquake Loading
Author(s):
Oguzhan Bayrak and Shamim A. Sheikh
Publication:
Structural Journal
Volume:
94
Issue:
6
Appears on pages(s):
708-722
Keywords:
deformability; ductility; energy dissipation capacity high-strength
concrete; member performance; sectional performance; stiffness;
strength; tied columns.
DOI:
10.14359/9731
Date:
11/1/1997
Abstract:
Main objectives of this research are to evaluate performance of high-strength concrete (HSC) columns for ductility and strength, and to criti-cally examine ACI’s Code requirements for confinement steel. Results from four HSC specimens with concrete strength of 72 MPa tested under simu-lated earthquake loading are presented here and compared with similar specimens made of normal strength concrete, (NSC). Each specimen con-sisted of a 305 x 305 x 1473 mm column and 508 x 762 x 813 mm stub which represented a discontinuity like a beam column joint or a footing. The variables studied in this research are the concrete strength, steel configuration, axial load level, amount of lateral steel, and the presence of a heavy stub. As in the case of normal strength concrete, an increase in the amount of lateral steel, reduction in axial load, and increased effectiveness of the lateral support provided to longitudinal bars resulted in increases in energy absorption and dissipation capacity as well as ductility. For a spec-i’ed column performance if the axial load measured as a fraction of P, is kept constant, the required amount of lateral steel appears to be propor-tional to the strength of concrete, in the 30 to 72 MPa strength range con-sidered in this study.