Unbonded post-tensioned precast concrete beam-column subassemblages have been studied in previous research and were found to be a promising seismic resistant structural system. The behavior of two ix-story unbonded post-tensioned frames is studied using nonlinear push-over static analyses and time-history dynamic analyses. Two analytical models are developed for the analyses; the fiber model and the spring model. The results show that the behavior of unbonded post-tensioned precast frames, in particular, the strength, ductility and self-centering capability is more than adequate for severe earthquake loading.
