Underground Blast Induced Vibration Control of Building Isolated with Shape Memory Alloy Friction Pendulum

Vibration control efficiency of shape memory alloy (SMA) assisted friction pendulum (SMA-FP) for building during blast induced ground motion (BIGM) has been explore here, and compared with the performance of conventional friction pendulum (FP) isolation system. This study analyzes the structural behavior of a five-storey steel shear building subjected to blast loading. To this end, nonlinear time-history analyses (NLTHA) are performed to evaluate the responses of the linear shear building structure isolated with the nonlinear base isolation (BI) system (either FP or SMA-FP). Study results shows that, the conventional FP BI system loses is peak floor acceleration control efficiency and shows large peak isolator displacement with noticeable residual displacement. Opposing to this, presence of SMA not only improves the isolator displacement and residual displacements, slightly reduces the peak floor acceleration. Furthermore, the study result reveals that, a particular combination of friction coefficient and SMA wire strength maximizes the isolator control efficiency i.e. minimizes the top floor peak acceleration. Such optimally designed SMA-FP isolator offers 3% higher top floor peak acceleration efficiency than FP isolator, whereas substantially reduces peak and residual isolator displacement by 37% and 6%, respectively. Finally, the enhanced control efficiency of SMA-FP BI over FP BI under the BIGM has been demonstrated through parametrical study, taking an inclusive range of building, isolators, and BIGM parameters.