Title: Effect of Axial Load Ratio and Stirrups Volume Ratio on Ductility of High-Strength Concrete Columns

Author(s): Q. Wang, G. Zhoo, and L. Lin

Publication: Symposium Paper

Volume: 149

Issue:

Appears on pages(s): 433-448

Keywords: axial loads; bending; columns (supports); compression; damage; ductility; high-strength concretes; shear properties; stirrups; Structural Research

DOI: 10.14359/4171

Date: 10/1/1994

Abstract:
Ductility of high-strength concrete columns is very important in the aseismic design. There are many factors affecting the ductility of compression-bending members. The axial load ratio and volume stirrups ratio are main factors. Based on the experimental research of reinforced concrete columns with high-strength and normal strength concretes under monotonic and cyclic loading, it can be observed that under different axial load ratio and stirrup volume ratio the damage pattern of members is different, and there is also obvious difference in the ductility. To control ductility of members, we must control the damage pattern. If the axial load ratio is high, the shear-compressive damage of the column should be avoided to provide the required ductility. On the basis of experiments, the mechanism of the effect of axial load ratio on the ductility of column is also discussed. The axial load ratio limits are proposed under the condition of limited ductility. The experiments show that the relationship between stirrup ratio and axial load ratio is not linear if the axial load ratio is high, which is different from previous research. In the design, a simplified bilinear relationship can be adopted that agrees well with the experimental results.