Energy dissipation and equivalent damping of RC columns subjected to biaxial bending: an investigation based in experimental results

Abstract

The cyclic behaviour of reinforced concrete columns have been object of many experimental studies in the recent past years. However, the experimental studies on the biaxial response of RC columns are still limited. In this paper are presented the main results of an experimental study of 24 full-scale rectangular building columns tested for different loading paths under uniaxial and biaxial conditions. The experimental results are presented and discussed in terms of global behaviour, particularly focusing on the stiffness and strength degradation due to the increasing cyclic demand, and energy dissipation evolution. The equivalent viscous damping was estimated based on the experimental results of the RC columns tested under biaxial loading and empirical expressions are proposed.