|
Abstract
|
The aim of this study is to investigate the dynamic performance of rectangular
and circular reinforced concrete (RC) columns considering biaxial multiple excitations.
For this purpose, an advanced nonlinear finite element model which can simulate various
features of cyclic degradation in material and structural components is used. The
implemented nonlinear fiber beam-column model accounts for inelastic buckling and
low-cycle fatigue degradation of longitudinal reinforcement and can simulate multiple
failure modes of RC columns under dynamic loading. Hypothetical rectangular and
circular columns are used to investigate the failure modes of RC columns. A detailed
ground motion selection is implemented to generate real mainshock and aftershocks. It
was found that multiple excitations due to aftershock has the potential of increasing the
damage of the RC columns and longitudinal reinforcements are significantly affected
low-cycle fatigue. Also, it was found that rectangular column is more sensitive to
accumulative damage due to cyclic fatigue. This study increases the accuracy of
structural analysis of RC columns and consequently improves understanding the failure
modes of RC columns with different cross-sectional shapes.
|