Inelastic response of bi-eccentric-plan asymmetric reinforced concrete buildings

Abstract

The inelastic seismic responses of plan asymmetric multi-storey reinforced concrete moment-resisting frames stiffened with ductile reinforced concrete structural walls have been investigated under bi-directional far-field and near-field ground motions. Asymmetric models were created by adding shear walls in two orthogonal directions of some symmetric frames developed using the generic structures algorithm. A realistic modelling of the non-linear ductile behaviour of reinforced concrete elements was utilised in combination with both mass and stiffness eccentricities in dynamic torsional response of asymmetric buildings. The torsional responses of models including the ductility demands for both stiff and flexible edge elements including shear walls and columns were normalised to the corresponding values of the symmetric models. The distribution of normalised ductility demands along the height of structures was used to assess the torsional effects in multi-storey structures. It was also shown that for dual lateral load-resistant systems, columns at the corners of flexible sides demand more ductility compared with similar frame systems.