Inherent ductility of non-seismically designed and detailed reinforced concrete frame buildings

A large-scale reinforced concrete sub-frame designed and detailed without seismic consideration, as practised in low probability of seismic occurrence regions, is tested under quasi-static cyclic loading. The seismic behaviour and available displacement ductility of the structure and structural members are investigated. The inherent ductility, derived from the egxperimental test, is compared with theoretical values for reliability check. The ductility demand factors of non-seismically designed and detailed ordinary moment resisting frames, subjected to low to moderate seismic events, has been evaluated and used as basis for the required estimate of ductility demands. Correlating the available ductility with the required ductility demands, it is concluded that an ordinary moment resisting frame could not possess the ductility to adequately respond to an unexpected low to moderate earthquake