Performance of circular hollow concrete columns with a single layer of transverse reinforcement

Abstract

Circular hollow concrete columns are preferably designed with a single layer of transverse reinforcement to withstand seismic loads considering both acceptable performance and ease of construction. However, both the confining effect and failure characteristics of hollow columns are different from the confining effect and failure of solid columns. To investigate the performance of circular hollow concrete columns with a single layer of transverse reinforcement, two large-scale column units were designed and tested. Their performance was evaluated in terms of displacement ductility, stiffness degradation, and energy dissipation. In addition, the confinement-induced strains in the transverse reinforcement within the plastic hinge regions were recorded to quantify the confining effect. To better simulate the responses of circular hollow concrete columns with a single layer of transverse reinforcement, a frequently used confined concrete model was improved, and its accuracy was validated by comparing the experimental and simulated responses at both global and local levels.