Numerical modelling of reinforced concrete walls with minimum vertical reinforcement contents

Abstract

Reinforced concrete (RC) structural walls are effective lateral force-resisting components that are commonly implemented in tall buildings. Recent studies have investigated the impact of minimum vertical reinforcement limits on the ductility at the plastic hinge region of RC walls and resulted in revisions to design standard requirements in both New Zealand and the United States. These studies focused on rectangular walls with a clear plastic hinge region at the wall base, whereas tall buildings exhibit more distributed plasticity demands up the wall height. In order to investigate the tall wall performance designed in accordance with the current standard, distributed plasticity beam-column fiber element was implemented to simulate the behaviour of the walls. The modelling technique was validated against the experimental tests with a range of vertical reinforcement contents to ensure a full range of wall sections can be accurately modelled. Following calibration and validation of the model, a push-over analysis was conducted on a 10-storey wall satisfying the minimum vertical reinforcement requirement over the full wall height to understand the wall critical section performance where the required additional reinforcement in the plastic hinge region terminates. The result obtained from this numerical study illustrated the upper storeys with the minimum required vertical reinforcement above intend plastic height are susceptible to unintended concentrations in in-elastic demands and fracture of vertical reinforcement.