Collapse fragility analysis of self-centering precast concrete walls with different post-tensioning and energy dissipation designs

Self-centering precast concrete walls have been known as an efficient low-damage lateral force resisting system for use in seismic regions. Previous studies have mainly focused on investigating the hysteretic behavior of the system through experimental and numerical simulation. This paper evaluates the influences of different post-tensioning (PT) and energy dissipation (ED) designs, which can be uniquely controlled by designers, on the collapse performance of self-centering precast concrete walls. Additionally, influences of different response reduction factors (R) and collapse criterion during design and analysis are also examined. For this respect, an example four-story self-centering precast wall building was designed and simulated using the numerical model verified according to reported test data. A total of eight different designs are considered for the example building with varying parameters of PT and ED designs, and R values. The analytical models are then subjected to a suite of 44 ground motions with each scaled up until the collapse occurs. The fragility curves are generated using the incremental dynamic analysis data, and the results are then used for collapse risk assessment in accordance with FEMA P695 procedure. The evaluation results show that ED designs have more influence than PT designs to the overall collapse fragility of self-centering precast walls. Nevertheless, all the prototype walls in this study are proved to have acceptably low probabilities of collapse, which is required by the design code.