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To overcome negative effects of traditional masonry infilling walls (MIWs) on the seismic resilience of a self-centering prestressed concrete (SCPC) frame, a novel SCPC frame with sliding infill walls (SCPC-SIW frame) is proposed. This study compares the seismic performance of the SCPC-SIW frame and the SCPC frame with MIWs (SCPC-MIW frame) through quasi-static tests, fragility analysis, and risk assessment. To begin, quasi-static tests on single-story SCPC-SIW and SCPC-MIW frame specimens are performed to compare their failure characteristics, hysteresis response, energy dissipation, and self-centering ability. The numerical simulation methods for SCPC-SIW and SCPC-MIW frame specimens are then presented and validated. Subsequently, two four-story SCPC-SIW frames and two four-story SCPC-MIW frames are designed, and their dynamic response under MCE is preliminary analyzed. Finally, the fragility analysis and risk assessment of these multi-story SCPC-SIW and SCPC-MIW frames are conducted to determine the probability of their peak inter-story drift ratio (PIDR), residual inter-story drift ratio (RIDR), and peak floor acceleration (PFA) exceeding the specified limit states under any intensity earthquake and within 50 years. The results indicate that, except for cracks caused by fatigue damage appearing on the SIW at the end of loading, the SCPC-SIW frame specimen remains undamaged, whereas the SCPC-MIW frame specimen exhibits diagonal step cracks on the MIW. The hysteresis curve of the SCPC-SIW frame specimen exhibits an ideal and repeatable flag shape, whereas the stiffness and strength of the SCPC-MIW frame specimen degrade during the test. Besides, the probability of exceeding the 4% PIDR and exceeding 0.2% and 0.5% RIDRs within 50 years for the SCPC-SIW frame is significantly lower than that for the SCPC-MIW frame. The SCPC25-MIW frame has a higher probability of exceeding the 1 g PFA within 50 years than the SCPC25-MIW frame. In other cases, the SCPC-SIW frame has a lower probability of exceeding 1 g, 2 g, and 3 g PFA within 50 years than the SCPC-MIW frame. [ABSTRACT FROM AUTHOR]

A self-centering viscous-hysteretic device (SC-VHD), composed of a viscous damper and ring springs in parallel, which combines velocity-proportional viscous energy dissipation and displacement-proportional hysteretic energy dissipation is studied. To evaluate the seismic behavior of structures with self-centering viscous-hysteretic devices and obtain appropriate parametric combinations between the main structure and the added self-centering viscous-hysteretic devices, a parametric study was conducted on SDOF elastoplastic structures with SC-VHDs. The results show that the SC-VHD can reduce about 30–50% of peak displacement and more than 80% of residual deformation, whilst a small increase in peak acceleration was observed. The reduction of the residual deformation is mainly influenced by the ring springs damping ratio and the ratio of preload to structural yielding strength, while the reduction of the peak displacement is significantly influenced by the viscous damping ratio and the ratio of loading stiffness to structural elastic stiffness. When the SC-VHD was designed with a viscous damping ratio of no less than 5%, a ring springs damping ratio of 15% at most, a ratio of preload to yielding strength of no less than 0.1 and a ratio of loading stiffness to elastic stiffness of no less than 0.1, the 2% peak drift and 0.2% residual drift criteria can be satisfied. Based on the parametric analysis results and an improved equivalent damping model parallel to ASCE 7, a displacement-based design method of SDOF elastoplastic structure was then proposed and evaluated by comparison with nonlinear time-history history analysis results. [ABSTRACT FROM AUTHOR]

This research presents a novel self-centering fluidic viscous damper that incorporates preloaded ring springs to offer self-centering capability and a fluidic viscous damper for energy dissipation. A full-scale self-centering fluidic viscous damper was developed and subjected to low-cyclic reversed loading tests. The test results show the self-centering fluidic viscous damper has both displacement-dependent and velocity-dependent hysteric responses with self-centering capability. Fatigue tests further show that the self-centering fluidic viscous damper maintains a stable hysteretic response under reversed loading. An analytical model and a numerical model are developed for the proposed self-centering fluidic viscous damper and analyzed. Comparisons of test results and the numerical and analytical models show similar hysteric responses, thereby validating the accuracy of the numerical and analytical models to simulate the behavior of the proposed damper. [ABSTRACT FROM AUTHOR]