Towards a low-damage seismic design: Developing and validating a performance-based design framework for segmental post-tensioned precast concrete piers

Segmental post-tensioned precast concrete (SPPC) piers show significant potential for enhancing post-earthquake rehabilitation, yet a practical performance-based seismic design framework remains undeveloped. In this respect, the current study develops and validates a comprehensive framework, demonstrating SPPC piers’ ability to minimize damage to individual pier components while maintaining the integrity of the overall bridge system. The framework employs a two-tier design methodology that integrates a capacity-demand-diagram approach with fragility analysis. The capacity-demand-diagram method is used to ensure that the displacement demands of the SPPC piers are consistent with predefined seismic displacement targets at the design earthquake level, thus facilitating the efficient determination of preliminary design parameters. Subsequently, fragility analysis is employed to assess the probability of failure, allowing iterative refinement of the design parameters to meet damage tolerance requirements. The developed framework is validated through a case study that compares SPPC piers with conventional piers in high-seismic regions. This step-by-step analysis confirms the applicability of the framework and shows that SPPC piers can be effectively integrated into current seismic design practices, supporting a performance-based framework with ease and reliability.