Seismic Vulnerability Assessment of Self-Centering Prestressed Concrete Frames with and without Masonry Infill Walls: Experimental and Numerical Models

Abstract

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.