Seismic performance of post-tensioned segmental precast concrete shear walls integrated with pinned steel frames

Despite extensive research on post-tensioned segmental precast concrete shear walls (PSPCSWs), limited attention has been given to seismic performance of hybrid lateral strength configurations that enable rapid constructability. Hence, this study investigates the seismic performance of PSPCSWs integrated with pinned steel frames, designed to facilitate rapid construction and to ensure self-centering capability for enhanced seismic resilience. In this configuration, the pinned steel frame primarily carries gravity loads, while the PSPCSW provides lateral resistance against seismic hazards. Prototypes of 4-, 8-, and 12-story buildings were designed for a high-seismicity region and selected 2-D frames analyzed using nonlinear static and dynamic procedures with an experimentally validated fiber-based numerical model in OpenSees. A suit of 40 ground motion records, scaled to an ASCE Site Class C Design Response Spectrum, were used to capture force, stress, shear friction coefficient, displacement, and acceleration demands. The results indicate that the proposed wall–frame system demonstrates favorable seismic performance. The steel frame remains elastic with negligible shear demand, fulfilling its intended role of resisting gravity loads. The tendons primarily remain elastic, while the concrete segments experience compressive stresses well below the crushing strength, contributing to the low residual drift ratios observed in the PSPCSW system. Overall, the system maintains acceptable drift ratios, shear-friction demands, and acceleration levels when evaluated against seismic code/standard recommendations (e.g., ASCE/SEI 7-22, ACI ITG-5.2, FEMA P-58) under median demands, although some ground motions exceed these limits. Notably, dynamic base shear demands consistently surpass static predictions due to higher-mode effects, particularly in taller systems, underscoring the inadequacy of classic first-mode-based design approaches. These findings highlight the need for supplemental energy dissipation strategies to mitigate unfavorable demands and enhance the system's overall seismic resilience. Since the study focuses on a system-level numerical investigation using an experimentally validated modeling framework rather than introducing new experimental testing, the numerical model is validated against experimental results from the PRESSS program, ensuring reliable representation of joint rocking, stiffness degradation, and hysteretic response.