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Interaction between masonry infill walls (MIWs) and a main structural system can impact the overall structural performance. However, there is no test to investigate the impact of MIWs on self-centering prestressed concrete (SCPC) frames, nor has there been a probabilistic performance evaluation considering the coupling effects of peak interstory drift ratio (PIDR) and residual interstory drift ratio (RIDR). This study compares the seismic performance of SCPC frames with and without MIWs through quasi-static tests and seismic risk assessment under mainshock–aftershock (MSAS) sequences. To begin, quasi-static tests on one-story SCPC frames with and without MIWs are performed to assess their seismic performance. A numerical simulation method for the SCPC frame with MIWs is then proposed and validated. Following that, the seismic performance of four multistory SCPC frames with and without MIWs is investigated under MSAS sequences at the maximum considered earthquake level. Finally, the seismic vulnerability assessment, considering the coupling effect of PIDR and RIDR under MSAS sequences, is conducted. The results indicate that cracks on the MIW present diagonal stepped cracks, and the MIW does not cause damage to the SCPC frame. When the MIW is damaged, the RIDR of the SCPC-MIW frame increases significantly; when the crack development is stable, the RIDR increases slowly as the interstory drift increases but remains at a very low level. Besides, when the MIW is damaged, an obvious deformation concentration effect occurs on the SCPC-MIW frame. The SCPC-MIW frame has a lower probability of exceeding the immediate occupancy level P(IO) than the SCPC frame, but it has a higher probability of exceeding the repairable level P(RE) when the seismic intensity is relatively small. Overall, the P(IO) and P(RE) of the SCPC and SCPC-MIW frames are higher under MSAS sequences than under MS-only sequences, except for the SCPC25 frame. [ABSTRACT FROM AUTHOR]

Double-story high-speed railway stations have become increasingly popular due to their smaller footprint and improved operational efficiency. However, ensuring passenger comfort in such stations requires careful consideration of train-induced vibrations. This study investigates the train-induced vibrations in Beijing Fengtai Railway Station, which is Asia's largest and China's first double-story high-speed railway station. To carry out this work, a vibration source load model and the finite-element model of the station were first established, where the model was verified using field-measured data. Following these, the vibration characteristics of the station under various train passing conditions, including different track positions and train speeds, were investigated numerically in both time and frequency domains. The findings of this study provide valuable insights for the vibration control of the railway stations of the similar modes and scales. [ABSTRACT FROM AUTHOR]

Shake-table tests, subjected to mainshock–aftershock sequences, were conducted on a 1/3-scaled 3-story steel frame equipped with self-centering viscous-hysteretic devices (SC-VHDs) and its primary frame to investigate the effect of the aftershock on seismic performance. It was found that the SC-VHD can effectively reduce 30%–50% of the peak drift and 50%–80% of the residual drift, respectively. Additionally, the peak and residual drifts of the 3-story primary frame under the mainshock–aftershock sequences were more than those under the mainshock-only sequences, while the peak and residual drifts of the 3-story SC-VHD frame under the mainshock-only and mainshock–aftershock sequences were basically the same. A numerical simulation method for the SC-VHD frame was further developed and validated, based on which 6-, 9-, and 12-story SC-VHD frames were analyzed to investigate the seismic performance of medium- high-rise SC-VHD frames. Both shake-table tests and numerical analysis indicate that the peak and residual drifts of the 3-, 6-, 9-, and 12-story SC-VHD frames can meet the design objective under the mainshock–aftershock sequences. [ABSTRACT FROM AUTHOR]