Effect of axial compression on ductility design of RC walls

Reinforced concrete (RC) structural walls can render excellent lateral stability and ductility to medium to high-rise buildings, but are generally subjected to very high axial compression loading, which can reduce the inherent ductility. A comprehensive statistical analysis with 474 sets of experimental data was conducted to evaluate and quantify the effect of the axial compression ratio (ACR) on the structural performance of RC structural walls. The stipulated limits on the ACR and the methods of evaluation used in various design codes were compared. Provisions on the limits of the ACR stipulated in various design codes were compared, and the expected attainable ductility factors for RC walls designed to different codes were evaluated. It was found that the provisions on ACR limits in Eurocode 8 generally satisfy the target ductility level but a distinction needs to be made between non-squat and squat walls due to their different structural behaviours.